To meet the demands of electric vehicles for range and power, drive motors are developing towards higher power density. However, due to the sharp increase in internal heat generation, problems such as insulation aging and demagnetization of permanent magnets occur, threatening the safety and lifespan of the motors. This article analyzes the application limitations of the existing air cooling、liquid cooling and oil cooling technologies for drive motors, explores the correlation between the structures of key components such as stators and rotors and the heat dissipation paths, proposes a structure-thermal management collaborative optimization strategy based on multi-physical field coupling, constructs a multi-objective optimization model by combining genetic algorithms and particle swarm optimization algorithms, and verifies the feasibility of the scheme through ANSYS finite element simulation and experiments. The results show that this strategy can effectively balance motor lightweighting, low temperature rise and high reliability, providing a reference for the development of the next generation of high-performance electric vehicle drive systems.