A high-voltage high-efficiency tube flameproof type threephase asynchronous motor is designed. The design advantages of the whole structure and the stator, frame, rotor, fan, bearing and junction box of the motor are introduced. The motor design shows innovation in the aspects of efficiency, circumferential eccentric tube arrangement, high strength flameproof parts, shaft through winding, thin oil lubricated rolling bearing, high protection, low vibration, low noise, etc. The advancement of the designed motor is proved by analyzing the test data of the product prototype.