Mossé was born the daughter of a wine merchant in Paris. She is the sister of Eliane Mossé, researcher in macroeconomics, and Arlette Mosse, clinical nutritionist. In the winter of 1941, during World War II and aged 16, she first read a text on liberty and democracy by Demosthenes; since then, she has dedicated her life to Greek history, never having married or having any children. Her favourite historical subject is 4th century BCE Athens. Mossé belongs to the same school of historical thought with Jean-Pierre Vernant and Pierre Vidal-Naquet. She is professor emeritus at the University of Paris VIII. Her works have been translated into many languages including English, German, Spanish, Italian and modern Greek.