Goldwater was born in Phoenix, in what was then the Arizona Territory, the son of Baron M. Goldwater and his wife, Hattie Josephine ("JoJo") Williams. His father's family had founded Goldwater's, a leading upscale department store in Phoenix. Goldwater's paternal grandfather, Michel Goldwasser, a Polish Jew, was born in 1821 in Konin, Poland, whence he emigrated to London following the Revolutions of 1848. Soon after arriving in London, he anglicized his name from "Goldwasser" to "Goldwater". Michel married Sarah Nathan, a member of an English Jewish family, in the Great Synagogue of London.

Goldwater's uncle Morris Goldwater (1852-1939) was an Arizona territorial and state legislator, mayor of Prescott, Arizona, and a businessman.

In 1916, Goldwater visited the Hopi Reservation with Phoenix Architect John Rinker Kibby, and obtained his first kachina doll. Eventually his doll collection included 437 items and was presented in 1969 to the Heard Museum in Phoenix.

Goldwater was an avid amateur radio operator from the early 1920s onwards, with the call signs 6BPI, K3UIG and K7UGA. The last is now used by an Arizona club honoring him as a commemorative call. During the Vietnam War he was a Military Affiliate Radio System (MARS) operator.

The family department store made the Goldwaters comfortably wealthy. Goldwater graduated from Staunton Military Academy, an elite private school in Virginia, and attended the University of Arizona for one year, where he joined the Sigma Chi fraternity. Barry had never been close to his father, but he took over the family Business after Baron's death in 1930. He became a Republican (in a heavily Democratic state), promoted innovative Business practices, and opposed the New Deal, especially because it fostered labor unions. Goldwater came to know former President Herbert Hoover, whose conservative politics he admired greatly.

In 1934, he married Margaret "Peggy" Johnson, wealthy daughter of a prominent industrialist from Muncie, Indiana. They had four children: Joanne (born January 1, 1936), Barry (born July 15, 1938), Michael (born March 15, 1940), and Peggy (born July 27, 1944). Goldwater became a widower in 1985, and in 1992 he married Susan Wechsler, a nurse 32 years his junior.

In 1940, Goldwater became one of the first people to run the Colorado River recreationally through Grand Canyon participating as an oarsman on Norman Nevills' second commercial river trip. Goldwater joined them in Green River, Utah, and rowed his own boat down to Lake Mead.

Goldwater was an amateur Photographer and in his estate left some 15,000 of his images to three Arizona institutions. He was very keen on candid photography. He got started in photography after receiving a camera as a gift from his wife on their first Christmas together. He was known to use a 4×5 Graflex, Rolleiflex, 16 mm Bell and Howell motion picture camera, and 35 mm Nikkormat FT. He was a member of the Royal Photographic Society from 1941 becoming a Life Member in 1948.

He entered Phoenix politics in 1949, when he was elected to the City Council as part of a nonpartisan team of candidates pledged to clean up widespread prostitution and gambling. The team won every mayoral and council election for the next two decades. Goldwater rebuilt the weak Republican party and was instrumental in electing Howard Pyle as Governor in 1950.

As a Republican he won a seat in the U.S. Senate in 1952, when he upset veteran Democrat and Senate Majority Leader Ernest McFarland. He won largely by defeating McFarland in his native Maricopa County by 12,600 votes, almost double the overall margin of 6,725 votes. As a measure of how Democratic Arizona had been since joining the Union 40 years earlier, Goldwater was only the second Republican ever to represent Arizona in the Senate. He defeated McFarland again in 1958, with a strong showing in his first reelection; he was the first Arizona Republican to win a second term in the Senate. Goldwater's victory was all the more remarkable since it came in a year the Democrats gained 13 seats in the Senate. He gave up re-election for the Senate in 1964 in favor of his presidential campaign.

Future Chief Justice of the United States and fellow Arizonan william H. Rehnquist also first came to the attention of national Republicans through his work as a legal adviser to Goldwater's presidential campaign. Rehnquist had begun his law practice in 1953 in the firm of Denison Kitchel of Phoenix, Goldwater's national campaign manager and friend of nearly three decades.

All this appealed to white Southern Democrats, and Goldwater was the first Republican to win the electoral votes of all of the Deep South states (South Carolina, Georgia, Alabama, Mississippi and Louisiana) since Reconstruction (although Dwight Eisenhower did carry Louisiana in 1956). However, Goldwater's vote on the Civil Rights Act proved devastating to his campaign everywhere outside the South (besides Dixie, Goldwater won only in Arizona, his home state), contributing to his landslide defeat in 1964.

Goldwater became most associated with labor-union reform and anti-communism; he was an active supporter of the conservative coalition in Congress. His work on labor issues led to Congress passing major anti-corruption reforms in 1957, and an all-out campaign by the AFL-CIO to defeat his 1958 reelection bid. He voted against the censure of Senator Joseph McCarthy in 1954, but he never actually charged any individual with being a communist/Soviet agent. Goldwater emphasized his strong opposition to the worldwide spread of communism in his 1960 book The Conscience of a Conservative. The book became an important reference text in conservative political circles.

Past comments came back to haunt Goldwater throughout the campaign. He had once called the Eisenhower administration "a dime-store New Deal", and the former President never fully forgave him. Eisenhower did, however, film a television commercial with Goldwater. Eisenhower qualified his voting for Goldwater in November by remarking that he had voted not specifically for Goldwater, but for the Republican Party. In December 1961, Goldwater had told a news conference that "sometimes I think this country would be better off if we could just saw off the Eastern Seaboard and let it float out to sea". That comment boomeranged on him during the campaign in the form of a Johnson television commercial, as did remarks about making Social Security voluntary, and statements in Tennessee about selling the Tennessee Valley Authority, a large local New Deal employer.

In 1963, he joined the Arizona Society of the Sons of the American Revolution. He was also a lifetime member of the Veterans of Foreign Wars, the American Legion, and Sigma Chi fraternity. He belonged to both the York Rite and Scottish Rite of Freemasonry, and was awarded the 33rd degree in the Scottish Rite.

The Republican Party recovered from the 1964 election debacle, picking up 47 seats in the House of Representatives in the 1966 mid-term election. Further Republican successes ensued, including Goldwater's return to the Senate in 1969. In January of that year, Goldwater wrote an article in the National Review "affirming that he [was] not against liberals, that liberals are needed as a counterweight to conservatism, and that he had in mind a fine liberal like Max Lerner".

Although Goldwater was not as important in the American conservative movement as Ronald Reagan after 1965, he shaped and redefined the movement from the late 1950s to 1964. Arizona Senator John McCain, who had succeeded Goldwater in the Senate in 1987, summed up Goldwater's legacy, "He transformed the Republican Party from an Eastern elitist organization to the breeding ground for the election of Ronald Reagan." Columnist George Will remarked after the 1980 Presidential election that it took 16 years to count the votes from 1964 and Goldwater won.

In the Batman TV series episodes "Hizzonner the Penguin" and "Dizzoner the Penguin," first aired on November 2, 1966 and November 3, 1966, respectively, Batman runs for Mayor of Gotham City against The Penguin. One of the other candidates in the race is "Harry Goldwinner," a monarchist candidate who receives 2% in the polls, because he is supported by "two old ladies."

For decades, he contributed photographs of his home state to Arizona Highways and was best known for his Western landscapes and pictures of native Americans in the United States. Three books with his photographs are People and Places, from 1967; Barry Goldwater and the Southwest, from 1976; and Delightful Journey, first published in 1940 and reprinted in 1970. Ansel Adams wrote a foreword to the 1976 book.

Goldwater remained popular in Arizona, and in the 1968 Senate election he was elected (this time) to the seat of retiring Senator Carl Hayden. He was subsequently reelected in 1974 and 1980. The 1974 election saw Goldwater easily reelected over his Democratic opponent, Jonathan Marshall, the publisher of The Scottsdale Progress. His final campaign in 1980 was close, with Goldwater winning in a near draw against Democratic challenger Bill Schulz. Goldwater said later that the close result convinced him not to run again.

Goldwater's son, Barry Goldwater Jr., served as a Congressman from California from 1969 to 1983. He was the first Congressman to serve while having a father in the Senate. Goldwater's uncle Morris Goldwater served in the Arizona territorial and state legislatures and as mayor of Prescott, Arizona. Goldwater's nephew, Don Goldwater, sought the Arizona Republican Party nomination for Governor of Arizona in 2006, but was defeated by Len Munsil.

Goldwater was an occasional roaster on the Dean Martin roasts of the mid-1970s.

Goldwater fought in 1971 to stop U.S. funding of the United Nations after the People's Republic of China was admitted to the organization. He said:

On March 28, 1975, Goldwater wrote to Shlomo Arnon: "The subject of UFOs has interested me for some long time. About ten or twelve years ago I made an effort to find out what was in the building at Wright-Patterson Air Force Base where the information has been stored that has been collected by the Air Force, and I was understandably denied this request. It is still Classified above Top Secret." Goldwater further wrote that there were rumors the evidence would be released, and that he was "just as anxious to see this material as you are, and I hope we will not have to wait much longer."

In 1979, when President Carter normalized relations with Communist China, Goldwater and some other senators sued him in the Supreme Court, arguing that the President could not terminate the Sino-American Mutual Defense Treaty with Republic of China (Taiwan) without the approval of Congress. The case, Goldwater v. Carter 444 U.S. 996, was dismissed by the court as a political question.

As a passionate defender of personal liberty, he saw the religious right's views as an encroachment on personal privacy and individual liberties. In his 1980 Senate reelection campaign, Goldwater won support from religious conservatives but in his final term voted consistently to uphold legalized abortion and, in 1981, gave a speech on how he was angry about the bullying of American politicians by religious organizations, and would "fight them every step of the way". Goldwater also disagreed with the Reagan administration on certain aspects of foreign policy (for Example, he opposed the decision to mine Nicaraguan harbors). Notwithstanding his prior differences with Dwight D. Eisenhower, Goldwater in a 1986 interview rated him the best of the seven Presidents with whom he had worked.

He introduced the 1984 Cable Franchise Policy and Communications Act, which allowed local governments to require the transmission of public, educational, and government access (PEG) channels, barred cable operators from exercising editorial control over content of programs carried on PEG channels, and absolved them from liability for their content.

The Barry M. Goldwater Scholarship and Excellence in Education Program was established by Congress in 1986. Its goal is to provide a continuing source of highly qualified Scientists, mathematicians, and Engineers by awarding scholarships to college students who intend to pursue careers in these fields.

He is a 1987 recipient of the Langley Gold Medal from the Smithsonian Institution. In 1988, in recognition of his career, Princeton University's American Whig-Cliosophic Society awarded Goldwater the James Madison Award for Distinguished Public Service.

In a 1988 interview on Larry King's radio show, Goldwater was asked if he thought the U.S. Government was withholding UFO evidence; he replied "Yes, I do." He added:

Goldwater visited the small town of Bowen, Illinois, in 1989 to see where his mother was raised.

Some of Goldwater's statements in the 1990s alienated many social conservatives. He endorsed Democrat Karan English in an Arizona congressional race, urged Republicans to lay off Bill Clinton over the Whitewater scandal, and criticized the military's ban on homosexuals: He said that "Everyone knows that gays have served honorably in the military since at least the time of Julius Caesar" and that "You don't need to be 'straight' to fight and die for your country. You just need to shoot straight." A few years before his death he addressed establishment Republicans by saying, "Do not associate my name with anything you do. You are extremists, and you've hurt the Republican party much more than the Democrats have."

Electronics was a hobby for Goldwater beyond amateur radio. He enjoyed assembling Heathkits, completing more than 100 and often visiting their maker in Benton Harbor, Michigan, to buy more, before the company exited the kit Business in 1992.

In a 1994 interview with The Washington Post, the retired senator said,

In 1996, he told Bob Dole, whose own presidential campaign received lukewarm support from conservative Republicans: "We're the new liberals of the Republican party. Can you imagine that?" In that same year, with Senator Dennis DeConcini, Goldwater endorsed an Arizona initiative to legalize medical marijuana against the countervailing opinion of social conservatives.

Goldwater's public appearances ended in late 1996 after he suffered a massive stroke; family members then disclosed he was in the early stages of Alzheimer's disease. He died on May 29, 1998, at the age of 89 at his long-time home in Paradise Valley, Arizona, of complications from the stroke. His funeral was co-officiated by both a reverend and a rabbi. His ashes were buried at the Episcopal Christ Church of the Ascension in Paradise Valley, Arizona. A memorial statue set in a small park has been erected to honor the memory of Goldwater in that town, near his former home and current resting place.

Goldwater's granddaughter, CC Goldwater, has co-produced with longtime friend and independent film Producer Tani L. Cohen a documentary on Goldwater's life, Mr. Conservative: Goldwater on Goldwater, first shown on HBO on September 18, 2006.

In response to Moral Majority founder Jerry Falwell's opposition to the nomination of Sandra Day O'Connor to the Supreme Court, of which Falwell had said, "Every good Christian should be concerned", Goldwater retorted: "Every good Christian ought to kick Falwell right in the ass." (According to John Dean, Goldwater actually suggested that good Christians ought to kick Falwell in the "nuts", but the news media "changed the anatomical reference.") Goldwater also had harsh words for his one-time political protegé, President Reagan, particularly after the Iran–Contra Affair became public in 1986. Journalist Robert MacNeil, a friend of Goldwater's from the 1964 Presidential campaign, recalled interviewing him in his office shortly afterward. "He was sitting in his office with his hands on his cane... and he said to me, 'Well, aren't you going to ask me about the Iran arms sales?' It had just been announced that the Reagan administration had sold arms to Iran. And I said, 'Well, if I asked you, what would you say?' He said, 'I'd say it's the god-damned stupidest foreign policy blunder this country's ever made!'", though aside from the Iran–Contra scandal, Goldwater thought nonetheless that Reagan was a good President. In 1988 during that year's presidential campaign, he pointedly told vice-presidential nominee Dan Quayle at a campaign event in Arizona "I want you to go back and tell George Bush to start talking about the issues."

Goldwater's photography interests occasionally crossed over with his political career. John F. Kennedy, as President, was known to invite former congressional colleagues to the White House for a drink. On one occasion, Goldwater brought his camera and photographed President Kennedy. When Kennedy received the photo, he returned it to Goldwater, with the inscription, "For Barry Goldwater—Whom I urge to follow the career for which he has shown such talent—photography!—from his friend – John Kennedy." This quip became a classic of American political humor after it was made famous by humorist Bennett Cerf. The photo itself was prized by Goldwater for the rest of his life, and recently sold for $17,925 in a Heritage auction.

Among the buildings and monuments named after Barry Goldwater are: the Barry M. Goldwater Terminal at Phoenix Sky Harbor International Airport, Goldwater Memorial Park in Paradise Valley, Arizona, the Barry Goldwater Air Force Academy Visitor Center at the United States Air Force Academy, and Barry Goldwater High School in northern Phoenix. In 2010 former Arizona Attorney General Grant Woods, himself a Goldwater scholar and supporter, founded the Goldwater Women's Tennis Classic Tournament to be held annually at the Phoenix Country Club in Phoenix. On February 11, 2015, a statue of Goldwater by Deborah Copenhaver Fellows was unveiled by U.S. House and Senate Leaders at a dedication ceremony in National Statuary Hall of the U.S. Capitol building in Washington, D.C. Barry Goldwater Peak is the highest peak in the White Tank Mountains.