Onzaga (Spanish pronunciation: [onˈsaɣa]) is a town and municipality in the Santander Department in northeastern Colombia.

Onzaga borders in the north San Joaquín, in the east and south the municipalities Soatá, Covarachía, Tipacoque and Tutazá of the department of Boyacá and in the west with Coromoro.

Onzaga is 177 kilometres (110 mi) south of the department capital Bucaramanga.

When the Spanish conquistadores arrived in the central highlands of Colombia, they found indigenous peoples expert in gold working and crafts.

[1] Main economical activities of Onzaga are the production of textile, shoes, liquor and agriculture (coffee, fique, maize, beans, sugar cane and yuca).