Roy Bean was born in 1825 in Mason County, Kentucky and was the youngest of five, (four sons and a daughter), of Phantly Roy Bean, Sr. and the former Anna Henderson Gore. The family was extremely poor and at age sixteen Bean left home to ride a flatboat to New Orleans hoping to find work. After getting into trouble in New Orleans, Bean fled to San Antonio, Texas to join his older brother Sam. Samuel Gore "Sam" Bean (1819–1903), who had earlier migrated to Independence, Missouri, was a teamster and bullwhacker. He hauled freight to Santa Fe and then on to Chihuahua, Mexico. After Sam fought in the Mexican–American War he moved out of San Antonio where his brother Roy joined him.In 1848 the two brothers opened a trading post in the Mexican state of Chihuahua. Soon after Roy Bean shot and killed a Mexican desperado who had threatened "to kill a gringo." To escape being charged with murder by Mexican authorities Roy and Sam Bean fled west to Sonora, Mexico. By the spring of 1849 Roy Bean had moved to San Diego, California, to live with his older brother Joshua Bean who would be elected the first Mayor of San Diego the following year.

Considered handsome Roy Bean competed for the attentions of various local women. A Scotsman named Collins challenged Bean to a pistol-shooting match on horseback. Bean was left to choose the targets and decided that they would shoot at each other. The duel was fought on February 24, 1852 and ended with Collins receiving a wound to his right arm. Both men were arrested and charged with assault with intent to murder. In the two months that he was in jail Bean received many gifts of flowers, food, wine and cigars from women in San Diego. Hidden in the final gifts he received while incarcerated were knives that were encased in tamales. Bean used the knives to dig through the cell wall and he escaped on April 17, 1852. He then fled to San Gabriel, California where he became a bartender in his brother's "Headquarters Saloon". After Joshua was murdered in November 1852 Bean inherited the saloon. In 1854 Bean courted a young woman who was subsequently kidnapped and forced to marry a Mexican officer. Bean challenged the groom to a duel and killed him. Six of the dead man's friends put Bean on a horse and tied a noose around his neck leaving him to hang when the horse moved. When he was hung the rope stretched and Bean was able to stay alive.The bride, who had been hiding behind a tree, cut the rope, freeing him and saving his life. This experience left Bean with a permanent rope burn and a stiff neck for the rest of his life. Shortly thereafter Roy Bean chose to leave California and migrated to New Mexico to live with Sam who had been elected the first sheriff of Doña Ana County. In 1861 Samuel G. and Roy Bean operated a store and saloon on Main Street in Pinos Altos (just north of Silver City) in present-day Grant County, New Mexico. It advertised liquor and "a fine billiard table." A cannon belonging to Roy Bean sat in front of the store for show and had been used to repel an Apache assault on the town.

During the Civil War the Confederate Army had invaded New Mexico. During the Battle of Glorieta Pass, in March 1862, the Confederates lost their supply wagons and were forced to retreat to San Antonio. After taking money from his brother's safe, Bean joined the retreating army. For the remainder of the war, he ran the naval blockade by hauling cotton from San Antonio to British ships off the coast at Matamoros and returning with needed supplies. For the next twenty years Bean lived in San Antonio, working nominally as a teamster. During this time he attempted to run a firewood Business by cutting down a neighbor's timber. He then tried to run a dairy Business but was soon caught watering down the milk. Bean later worked as a butcher rustling unbranded cattle from other area ranchers for his Business.

On October 28, 1866, he married eighteen-year-old Virginia Chavez. Within a year after being married he was arrested for aggravated assault and threatening his wife's life. Despite the tumultuous marriage, they had four children together - Roy Jr., Laura, Zulema and Sam. The family lived in what was described as "a poverty-stricken Mexican slum area called Beanville". Beanville would have been centered near the current day corner of South Flores Street and Glenn Avenue not far from Burbank High School. By the late 1870s Bean was operating a saloon in Beanville and had heard that many construction camps were opening as several railroad companies were working to extend the railroads west. A store owner in Beanville "was so anxious to have this unscrupulous character out of the neighborhood" that she bought all of Bean's possessions for $900 so that he could leave San Antonio. At the time Bean and his wife were separated and he left his children with friends as he prepared to go west.

One of his first acts as a justice of the peace was to "shoot [...] up the saloon shack of a Jewish competitor". Bean then turned his tent saloon into a part-time courtroom and began calling himself the "Law West of the Pecos." As a judge Bean relied on a single law book, the 1879 edition of the Revised Statutes of Texas, and when newer law books showed up he used them as kindling. Bean did not allow hung juries or appeals. Jurors, who were chosen from his best bar customers, were expected to buy a drink during every court recess. He was also known for his unusual rulings. In one case an Irishman named Paddy O'Rourke shot a Chinese laborer and during the trial a mob of 200 angry Irishmen surrounded the courtroom and saloon. They threatened to lynch Bean if O'Rourke was not freed and after looking through his law book Bean ruled that "homicide was the killing of a human being; however, he could find no law against killing a Chinaman" dismissing the case. On another occasion, upon finding the corpse of a man who had been carrying concealed weapons and USD$40 on his person when he had died, he imposed a posthumous USD$20 fine upon the man for having carried the concealed weapons. Bean, whose court/saloon was in need of money at the time, also collected a burial fee of USD$10 and USD$10 in court costs.

By December 1882 railroad construction had moved farther westward and Bean moved his courtroom and saloon 70 miles (110 km) to Strawbridge. He sent for his children who then lived with him at the saloon with his youngest son Sam sleeping on a pool table. A competitor, who was already established in the area, laced Bean's whiskey with Kerosene. Unable to attract customers Bean left the area and moved to Eagle's Nest, 20 miles (32 km) west of the Pecos River, which was soon renamed Langtry.

The original owner of the land, who ran a saloon, had sold 640 acres (2.59 km) to the railroad on the condition that no part of the land could be sold or leased to Bean. O'Rourke, the Irishman whose case Bean had previously dismissed, told Bean to use the railroad right-of-way which was not covered by the contract and for the next 20 years Bean squatted on land he had no legal right to use. Bean named his new saloon The Jersey Lilly in honor of Lillie Langtry who recounted in her autobiography that she had visited the area after Bean's death. Langtry did not have a jail and all cases were settled by fines. Bean refused to send the state any part of the fines and kept all of the money. In most cases the fines were made for the exact amount the accused's person had with them. During his term as a judge Bean is known to have sentenced only two men to hang with one of whom escaped. Horse thieves, who were often sentenced to death in other jurisdictions, were always let go if the horses were returned to their owners. Although only district courts were legally allowed to grant divorces Bean did so anyway and pocketed $10 for each divorce. He charged $5 for weddings and ended all wedding ceremonies with the phrase "and may God have mercy on your souls" (a traditional saying when a death sentence is carried out). Bean won re-election to his post in 1884 but was defeated in 1886. The following year the commissioner's court created a new precinct in the county and appointed Bean to be the new justice of the peace. He continued to be re-elected until 1896. Even after that election defeat he "refused to surrender his seal and law book and continued to try all cases north of the tracks".

In 1890, Bean received word that railroad developer and speculator Jay Gould was planning to pass through Langtry on a special train. Bean flagged down the train using a danger signal. Thinking the bridge was out the train Engineer stopped the train. Bean then invited Gould and his daughter to visit the saloon as his guests. The Goulds visited for two hours, causing a brief panic on the New York Stock Exchange when it was reported that Gould had been killed in a train crash. In 1896 Bean organized a world championship boxing title bout between Bob Fitzsimmons and Peter Maher on an island in the Rio Grande because boxing matches were illegal in both Texas and Mexico. The fight, won by Fitzsimmons, lasted only 1 minute and 35 seconds but the resulting sport reports spread Bean's fame throughout the United States. In the last years of his life Bean met surveyor and civil Engineer W. D. Twichell. Based primarily in Amarillo and later Austin Twichell surveyed 165 of the 254 Texan counties. As he aged, Bean spent much of his profits helping the poor of the area and always made sure that the local schoolhouse had free firewood in winter. Roy Bean died peacefully in his bed on 16 March 1903 after a bout of heavy drinking in San Antonio. He and his son, Sam Bean (1874–1907), are interred at the Whitehead Memorial Museum in Del Rio. In 1965, as part of the Civil War Centennial commemoration in Texas, an official Texas Historical Marker honoring Roy Bean was erected on the museum grounds in Del Rio, Texas.