To provide a vehicular main electric motor which is configured by general components in general size, and simplifies the replacing of a bearing.

In a vehicular main electric motor 100, on a cylindrical stator frame 101 provided with a side plate at one end and a flange surface of the stator frame 101, a bearing bracket 104 is attached. At both ends of a rotor shaft 105 (1) provided at a center of the stator frame 101, a cylindrical roller bearing 112 and a ball bearing 113 are provided at centers of a cylindrical roller bearing box 108 attached to the bearing bracket 104 and a ball bearing box 109 attached to the side plate of the stator frame 101. A cover 110 of the cylindrical roller bearing box and a cover 111 of the ball bearing box are fixed from the inside of a device. A cooling fan 106 on the cylindrical roller bearing side and a cooling fan 107 on the ball bearing side are connected to both ends of a rotor core 105 (2) in which the rotor shaft 105 (1) is inserted.