Abstract: As an important part of advanced solid engines, the load-bearing ability of filament-wound composite casings affects the overall performance of the engine directly. A simulation and analysis system for composite casings was developed based on the Open CASCADE (OCC) platform. Taking a diameter Φ 480 mm casing as the research object, a parametric simulation model for composite casings was constructed. Building upon this foundation, the influence of the ellipsoidal ratio and the cylindrical section length on the stress distribution of the casing was investigated in depth and a hydraulic burst tests were conducted for validation. The simulation results show that the stress fluctuation at the head of the casing decreases first and then increases with the increase of the ellipsoid ratio, and when the ellipsoid ratio is 1.7, the stress distribution is close to that of the equal stress head, which is more uniform. When the length of the barrel is too small, due to the mutual influence of the meridional bending moments at the front and rear equatorial circles, the negative stress phenomenon occurs in the direction of the spiral fiber of the barrel body. The research results will provide a theoretical reference for the selection of design parameters of composite casing structures.