The Golfo San Jorge Basin (Spanish: Cuenca del Golfo San Jorge) is a hydrocarbon-rich sedimentary basin located in eastern Patagonia, Argentina.

The basin has largely developed under condition of extensional tectonics, including rifting.

[1] The basin is of paleontological significance as it hosts six out of 22 defining formations for the SALMA classification, the geochronology for the Cenozoic used in South America.

At the center of the basin accumulated sediments reach more than 8,000 metres (26,000 ft) of thickness.

[1] The stratigraphy of the Golfo San Jorge Basin covers the following units:[1][2][3]