Massarelos (Portuguese pronunciation: [mɐsɐˈɾɛluʃ]) is a former civil parish in the municipality of Porto, Portugal. In 2013, the parish merged into the new parish Lordelo do Ouro e Massarelos. The population in 2011 was 6,789, in an area of 1.94 km².
The municipality includes parts of the city's old downtown, classified by UNESCO as a World Heritage Site. Other landmarks include Porto's main Custom House, Rosa Mota sports hall, Porto's major fish market and the Campo Alegre neighborhood, where a theatre and several buildings of the University of Porto are located.