Filament-wound composites are more and more frequently used for pressure tanks and motor cases. It is essential to study their mechanical properties, especially the properties at peculiar shaped locations. A carbon fiber wound pressure vessel structure was chosen to investigate by experiment and finite element method in our program, respectively. Considering the vessel deformation, internal pressure load was added step by step so that the changing stiffness matrix and changing geometric conditions could be calculated in simulation process. In our experiment, the pressure vessel with strain gauges was tested under internal pressure to get strain data at some typical locations. And a finite element model was built with software ANSYS considering the structural deformation of the pressure vessel. Under internal pressure, it is found that fibers in the cylinder part of the vessel are in tension and fibers in partial dome region are bent and transversely compressed. The simulated results also are in good agreement with experimental results.