The developments of TQ250 permanent magnet synchronous traction motor for next generation metro vehicles were introduced. The overall technical requirements, design difficulties, key technologies, prototype test and other aspects were mainly discussed. According to the technical characteristics and main technical parameters of permanent magnet synchronous traction motor for next generation metro vehicles, the design of the permanent magnet synchronous traction motor was improved by tackling key technical problems such as equivalent quota design, electromagnetic design, lightweight design and cooling structure design. A prototype was developed and the test was carried out on it. The results show that the motor meets the requirements of the next generation metro vehicles,and verify the feasibility of the design.