Casasimarro is a municipality in the province of Cuenca, in the autonomous community of Castile-La Mancha, Spain.

The area has an altitude of 750 meters and a continental climate (40º C in summer and -10º C) in winter. As of 2003, the town had a population of just over 3000.

The area is based around agriculture and cattle raising, with the main produce being mushrooms, cereals, wine and olive oil. Industries include guitar- and carpet-making.