John Thomas Jost (born 1968) is a social psychologist best known for his work on system justification theory and the psychology of political ideology. Jost received his AB degree in Psychology and Human Development from Duke University (1989), where he studied with , , and Lynn Hasher, and his PhD in Social and Political Psychology from Yale University (1995), where he was the last doctoral student of Leonard Doob and William J. McGuire. He was also a student of Mahzarin R. Banaji and a postdoctoral trainee of Arie W. Kruglanski.