In response to the growing demand for aviation power systems in multi-electric aircraft, a high-speed solid-core permanent magnet synchronous motor with a rated power of 75 kW and a rated speed of 65 000 r/min is designed in this paper. The type of high-speed motor operates at high speeds and has a high loss density, and its design is constrained by multiple physical fields. The motor performance, rotor strength, and cooling system are designed from three perspectives: electromagnetic field, mechanical field, and temperature field, through finite element simulation. And the accuracy and rationality of the design is verified by experimental results. The analysis results provide a reference for the motor products of the multi-electric aircraft power generation system.