PURPOSE: To provide a space robot joint temperature controller that is able to shorten a span of time for raising a joint temperature from a stand-by temperature to an operating one and simultaneously to reduce the extent of heating power.

CONSTITUTION: At the time of being on standby, a joint is heated by a heater 13, and at the time of operation starting, d.c. voltage of a heater power source is impressed on a coil of a motor 11 and this motor 11 is heated from the inside in addition to heater operation, and a fact that it is reached to the specified temperature is detected by a temperature sensor 14 and then the motor 11 is made so as to be selected to the side of a motor driving circuit 30.