San Justo is the Spanish name for Saint Justus.
As a place-name, San Justo may refer to:
San Justo, Santa Fe, the main township of San Justo Department, Argentina San Justo Department (disambiguation), various places San Justo, Buenos Aires, a town in La Matanza Partido, Argentina San Justo, Entre Ríos, a town in Entre Ríos, Argentina San Justo, Zamora, a municipality in the province of Zamora, Spain
San Justo may also refer to: Spanish ship San Justo