Phoebe Wolkind was born in the Bronx, New York, to a Jewish-American family. She graduated from James Monroe High School and Hunter College. In 1934, she married Henry Ephron, whom she met while both were counselors at a summer camp. The two were literary collaborators for nearly 40 years, co-writing Broadway plays and Hollywood films. They had four daughters, Nora, Delia, Amy, and Hallie Ephron. Their first hit play was Three’s a Family (1943), based on their experiences raising their firstborn, Nora. Shortly afterwards, the family moved to Los Angeles, where Phoebe and Henry wrote movie scripts, specializing in light romantic comedies and musicals. The 1957 film Desk Set, starring Spencer Tracy and Katharine Hepburn (His Other Woman in the UK), assured their success.
For Captain Newman, M.D. (1963), they received an Academy Award nomination. In their own screenplay for This Is My Life, Delia and Nora Ephron wrote about Dottie Ingel -- a character loosely based on their mother -- who offered witty "life lessons" to her children.
Nora Ephron once said that her mother understood that the "tragedies of your life one day have the potential to be comic stories the next." In 1977, Henry Ephron wrote a book about his collaboration with Phoebe, We Thought We Could Do Anything.