A cooling mechanism for a vehicle electric motor. The cooling mechanism includes: a coolant oil passage provided between a rotor core and a rotor shaft of the electric motor; an oil supply passage provided inside the rotor shaft and communicating with the coolant oil passage; and at least one first discharge port and at least one second discharge port provided in respective first and second end plates disposed on respective opposite sides of the rotor core. The coolant oil passage includes a first passage portion communicating with the at least one first discharge port, and a second passage portion communicating with the at least one second discharge port. Each of the at least one first discharge port is located in a position that is different from a position of any one of the at least one second discharge port as seen in an axial direction of the rotor shaft.