San Justo is a city in the center region of the province of Santa Fe, Argentina, 99 km north from the provincial capital.

It had about 22,000 inhabitants at the 2010 census [INDEC] and it is the head town of the San Justo Department.

Founded in 1868 by Mariano Cabal, San Justo attained the status of a comuna (commune) on 13 July 1887 and the following year the Ferrocarril Provincial de Santa Fe arrived on 1 September 1888.

On January 10, 1973, the town was struck by a destructive tornado.

This article about a place in Santa Fe Province, Argentina is a stub.