Markopoulo Oropou is a town and a former community of East Attica, Greece. Since the 2011 local government reform it is part of the municipality Oropos, of which it is a municipal unit. The municipal unit has an area of 23.177 km².

Markopoulo Oropou is situated 3 km south of the South Euboean Gulf coast. It is 4 km southeast of Nea Palatia