Alda was born Arlene Weiss in the Bronx, New York City to Jewish parents. She attended Evander Childs High School and Hunter College, graduating in January 1954 as a music major, Phi Beta Kappa, Cum Laude. Weiss was a recipient of a Fulbright Scholarship to Cologne, Germany, where she studied clarinet at the 'Kölnische Hochschule für Musik'. On her return to New York, she became a member of the National Orchestra, a training orchestra, conducted by Leon Barzin. She studied clarinet with Abraham Goldstein and Leon Russianoff, becoming a member of the Houston Symphony Orchestra, playing assistant first clarinet and bass clarinet under the baton of Leopold Stokowski.

Alda is married to actor Alan Alda. They wed on March 15, 1957, and they have three daughters, Eve (b. 1958), Elizabeth (b. 1960), and Beatrice (b. 1961), as well as eight grandchildren.

She is also represented in photo anthologies, Women of Vision, and Soho Gallery 2. Alda is the author of On Set (Fireside/Simon and Schuster 1981) illustrated with over one hundred of her photographs and The Last Days of Mash (Unicorn, 1983) with photos by Alda and co-written with her husband, Alan Alda. Her most recent book, Just Kids from the Bronx (Henry Holt and Co. March 2015.) an Oral History of 64 interviews with prominent Bronxites. The story tellers include Al Pacino, Regis Philbin, Colin Powell, Neil deGrasse Tyson, Mary Higgins Clark, Avery Corman, Chazz Palminteri, TATS CRU Graffiti Artists, Grandmaster Melle Mal, and the others, from age 93 to age 23.

Alda is the author of 15 children's books, including the best seller, Sheep, Sheep Sheep, Help Me Fall Asleep (Doubleday Books for Young Readers, 1992), Arlene Alda's 1,2,3 (Tricycle Press 1998), which won an American Library Notable citation, The Book of ZZZs (Tundra 2005), Did You Say Pears? (Tundra 2006) and Except the Color Grey (Tundra 2011). She also wrote the popular Hurry Granny Annie (Published by Tricycle Press in 1999) as well as Hold the Bus (Published by Troll Press in 1996), Iris Has a Virus (2008) and Lulu's Piano Lesson (2010). For much, but not all, of her career as an author, she has provided her own photography as illustrations used in her children's books.