Unión is a village and municipality in San Luis Province, Argentina, it is located at the intersection of National Route 188 and Provincial Route 3, in the southern of the province.

[1] National Route 188 connects Unión to General Alvear, 162 km (101 mi) to the west, and Realicó, 156 km (97 mi) to the east.

Provincial Route 3 connects Unión to San Luis City, 230 km (140 mi) to the north, and La Pampa Province, 101 km (63 mi) to the south.

Unión had a railway station opened in 1907 and abandoned in 1977.

This article about a place in San Luis Province, Argentina is a stub.