Three-dimensional modeling was carried out through CATIA software, fluid domain was extracted u-sing Space Claim module, fluid boundary conditions were set in Fluent module, and flow simulation was car-ried out. Ansys Workbench steady-state thermal and static stress analysis modules were successively intro-duced to set thermal boundary conditions and stress loads. The temperature field of the cylinder head and the coupled stress distribution of the thermal structure are obtained. The thermal structure coupling stress analysis shows that the maximum thermal strain is in the nasal bridge area of the fire surface, the maximum deformation is 0.0021 mm, the maximum stress is in the nasal bridge area between the two exhaust valves, the maximum stress value is 398 MPa, and the safety factor is 2.71, which meets the requirements of the actual structure work.