Castelo Viegas is a former civil parish in the municipality of Coimbra, Portugal. The population in 2011 was 1,695, in an area of 7.11 km<sup>2</sup>. On 28 January 2013 it merged with Santa Clara to form Santa Clara e Castelo Viegas.
The first mention is in 1122 with the name Castel Venegas.