Santa Cruz (Spanish pronunciation: [santa ˈkɾus]) is a province of Argentina, located in the southern part of the country, in Patagonia. It borders Chubut province to the north, and Chile to the west and south, with an Atlantic coast on its east. Santa Cruz is the second-largest province of the country (after Buenos Aires province), and the least densely populated in mainland Argentina.

The indigenous people of the province are the Tehuelches, who despite European exploration from the 16th century onwards, retained independence until the late 19th century. Soon after the Conquest of the Desert in the 1870s, the area was organised as the Territory of Santa Cruz, named after its original capital in Puerto Santa Cruz. The capital moved to Rio Gallegos in 1888 and has remained there ever since. Immigrants from various European countries came to the territory in the late 19th and early 20th century during a gold rush. Santa Cruz became a province of Argentina in 1957.