Mezalocha is a municipality in the province of Zaragoza, in the autonomous community of Aragon, Spain. It is located in the comarca of Campo de Cariñena, roughly 40 kilometres southwest of the city of Zaragoza.
The municipality covers a small area of rolling terrain typical of the Ebro basin, with dryland farming—principally cereals, vines and olives—forming the basis of its traditional economy. The village settlement is compact, centred on a modest church and a few stone houses characteristic of the region's rural architecture.
Mezalocha is a very small community: according to the 2025 census (INE), the municipality has 197 inhabitants. Like many villages in inland Aragon, it has experienced steady depopulation over the twentieth and twenty-first centuries as residents moved to larger urban centres.