Abstract: As an important part of advanced solid engines, the load-bearing performance of filament-wound composite shells affects the overall performance of the engine directly. Based on the Open CASCADE (OCC), a simulation and analysis system for composite shells was developed, and parametric simulation models of composite shells were constructed focusing on Φ480 mm shells, whose stress distribution law influenced by ellipsoidal ratio and barrel length was deeply explored, and the experimental verification was carried out. The simulation results show that the stress fluctuation at the head of the shell 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 shell structures.