In 1961, Walker entered Spelman College in Atlanta, Georgia and immediately became involved in the civil rights movement. In 1963, she went on to Sarah Lawrence College, where she began to develop her gift for poetry. Many of her poems were published in her first collection, Once (1968). In 1967, she married the Jewish civil rights lawyer Melvyn Leventhal, with whom she had worked to further blacks' rights in Mississippi. Her second novel, Meridian (1976), which describes a woman's activity in the civil rights movement, won considerable attention.

In her books, Walker extended her attacks on racial injustice to castigate the sexism she observed in some black American relationships. For this she was accused of distracting attention from the political oppression of black Americans at a time when the civil rights movement was beginning to make real headway. However, she was undeterred by criticism, and continued to expose the oppression of black women in sexual as well as political situations. In The Color Purple (1982), she drew a searing picture of sexual abuse within a context of white racism, depicting the search for selfhood of the central figure, Celie, and her emergence as a strong creative individual through friendship with other women. The novel won public and critical acclaim and was awarded both a National Book Award and a Pulitzer Prize. In 1985, it was adapted for the cinema by Steven Spielberg.