Leo Strauss (/straʊs/; German: [ˈleːo ˈʃtʁaʊs]; September 20, 1899 – October 18, 1973) was a German-American political philosopher and classicist who specialized in classical political philosophy. Born in Germany to Jewish parents, Strauss later emigrated from Germany to the United States. He spent much of his career as a professor of political science at the University of Chicago, where he taught several generations of students and published fifteen books.

Trained in the neo-Kantian tradition with Ernst Cassirer and immersed in the work of the phenomenologists Edmund Husserl and Martin Heidegger, Strauss established his fame with path-breaking books on Spinoza and Hobbes, then with articles on Maimonides and Farabi. In the late 1930s his research focused on the rediscovery of esoteric writing, thereby a new illumination of Plato and Aristotle, retracing their interpretation through medieval Islamic and Jewish philosophy, and encouraging the application of those ideas to contemporary political theory.