The invention relates to a traction motor for locomotives, in particular to a self-ventilating motor with high-efficiency cooling and heat dissipation. High-efficiency cooling and heat-dissipating self-ventilated motor, including rotor, base, and end cover, wherein the rotor includes a rotating shaft and a centrifugal fan, the base includes a stator core and a casing, and the casing is provided with an outer circular air inlet and an outer circular air outlet. There is an air inlet on the cover, the stator core is fixed on the casing through ribs, there is a ventilation space between the stator core and the inner wall of the casing, and there is an axial ventilation hole on the rotating shaft, thus forming four air passage structures. The heat source stator winding, stator core, bearing and rotor core in the motor with the unique cooling air path structure of the present invention are well cooled, and the generated heat can be well taken away. The motor with the structure of the invention has the characteristics of excellent cooling and heat dissipation capacity, and is especially suitable for the performance requirements of the traction motor by vehicle users.