Morgan was born in Lake Worth, Florida to Jewish parents [1] and grew up in Mount Vernon, New York. She began her career as a child star at the age of 2, when her mother and her Aunt Sally put her in child modelling. At the age of four she had her own radio program, Little Robin Morgan, and her most famous role came at the age of nine, when she began to play Dagmar Hansen, the younger sister in the 1950s TV series Mama which starred Peggy Wood. She was also an activist of the gay rights of women.

When she left the series in 1956, Morgan was suffering from the pressures of wealth and fame, and decided she would rather be a poet/writer than an actor. She fought her mother's efforts to force her to continue acting. She decided to study at, and was accepted to Columbia University but left before obtaining a degree, choosing to work as an agent occasional editor.

Morgan began publishing her poetry in the early 1960s (later collected in her 1972 anthology, Monster). In 1962, she married the poet Kenneth Pitchford. She soon became active in the anti-war Left, and contributed articles and poetry to Left-wing and counter-culture journals such as Liberation, Rat, Win, and The Guardian.

In the late 1960s, Morgan was a member of the Youth International Party with Abbie Hoffman and Paul Krassner. However, tensions over sexism within YIP (and the New Left in general) came to a head while Morgan was becoming more involved in Women's Liberation activism. In 1968, she joined demonstrations to free Valerie Solanas (protesting the three-year sentence Solanas received for attempted murder against Andy Warhol), and became a founding member of New York Radical Women, helping to organize their inaugural protest of the Miss America pageant in September 1968.

Later in the same year she helped to create W.I.T.C.H., a radical feminist group that used public street theater (called "hexes" or "zaps") to call attention to sexism. In December 1968, Morgan and other women staged a "hex" against both the House Unamerican Activities Committee and the Chicago Eight; they argued that the men in the HUAC and the Chicago Eight played off of each other to portray the antiwar movement as the pet project of a few male "stars."

Like many radical feminists, Morgan made a decisive break from what they described as the "male Left," and put the reasons for her break into her 1970 essay for the first women's issue of Rat, "Goodbye to All That." In the same year, she edited one of the first anthologies of radical feminist writings, Sisterhood is Powerful.

Since the 1970s, Morgan has continued in her writing, editing, publishing, and feminist organizing. In addition to her poetry and frequent articles on feminist topics, she has edited two anthologies following up on Sisterhood is Powerful: Sisterhood is Global (1984) and Sisterhood is Forever (2003). She has served as a contributing editor to Ms. Magazine for many years, and served as editor-in-chief from 1989-1993.

Robin Morgan currently lives in Manhattan. Her son (with Kenneth Pitchford) is the musician and recording artist Blake Morgan.