Oliveira do Bairro () is a town and a municipality in the district of Aveiro in Portugal. The population in 2011 was 47,729, in an area of 335.27 km<sup>2</sup>. It had 16,994 eligible voters in 2006. The town itself had a population of 3,077 in 2001.
The municipality is in the Bairrada area. The present Mayor is Duarte Novo. The municipal holiday is Ascension Day.
Administratively, the municipality is divided into 4 civil parishes (freguesias):
Oliveira do Bairro is twinned with two cities: