To make an electric caster of a carriage for stage setting have a simple constitution for miniaturization and to easily change a moving direction of the carriage.

This electric caster 1 is provided with a lower frame 4 provided with a pair of wheels (left and right wheels 2 and 3) and a rotary table 5 rotatably mounted on the lower frame 4 and fixed to a base plate, etc. of the carriage. The pair of wheels 2 and 3 are connected to each of a pair of motors 11 and 14 provided between the wheels 2 and 3. The pair of motors 11 and 14 are connected to an inverter in parallel. A switching means to switch a rotating direction of the one motor 14 is provided between either one motor 14 of the pair of motors 11 and 14 and the inverter. By rotating the pair of motors 11 and 14 in the same direction, the carriage is moved in a prescribed direction. By mutually rotating the pair of motors 11 and 14 in opposite directions, the electric caster 1 is rotated, and the moving direction of the carriage is changed.