Capital is a department in San Juan Province, Argentina.
The capital of San Juan has an area of . To the north bordering department Chimbas, on the east by Santa LucÃÂa, to the west and south by Rivadavia Rawson. The approximate population of the department of capital is 118,500 inhabitants.
According to estimates from INDEC, the national institute responsible for censuses, it had 116,511 inhabitants in 2005.