Casimcea is a commune in Tulcea County, Northern Dobruja, Romania.

The commune also included the village of Stânca (historical name: Mahomencea), located at 44°45′00″N 28°17′00″E / 44.75°N 28.2833°E / 44.75; 28.2833, which is currently deserted.

The name of the commune is of Turkish origin, being derived from the word Kasım, itself from the Arabic Qasim, "one who distributes".

The river Casimcea has its source in Războieni village, at an altitude of 300 m (980 ft), and flows southeast through Casimcea village, discharging in Lake Tașaul, close to the Black Sea coast.

The river Topolog flows through Rahman village, discharging further south into the Danube.