Simone de Beauvoir was a French existentialist philosopher, writer, social theorist, and feminist activist. Though she did not consider herself a philosopher, she had a significant influence on feminist existentialism and feminist theory.

Beauvoir wrote novels, essays, biographies, autobiographies, and monographs on philosophy, politics, and social issues. She was best known for her "trailblazing work in feminist philosophy", The Second Sex (1949), a detailed analysis of women's oppression and a foundational tract of contemporary feminism. Her novels include She Came to Stay (1943) and The Mandarins (1954).

Her most enduring contributions to literature are her memoirs, notably the first volume, Mémoires d'une jeune fille rangée (1958). She received the 1954 Prix Goncourt, the 1975 Jerusalem Prize, and the 1978 Austrian State Prize for European Literature. She was nominated for the Nobel Prize in Literature in 1961, 1969, and 1973.

Beauvoir's lifelong companion was philosopher Jean-Paul Sartre. Together, they were influential figures in French intellectual circles.