Abstract The pressure hull is a significant structural component of underwater vehicles, to enable them to withstand environmental loadings such as hydrostatical pressure. Geometric configurations such as hull shape, shell thickness, stiffener layout, and type of construction materials are the key factors influencing the structural performance of pressure hulls. This study aims to maximize the structural efficiency of elliptical deep-submerged pressure hull under hydrostatic pressure. Minimize the buoyancy factor of a submarine pressure hull under hydrostatic pressure was proposed as an objective function to achieve Minimum Weight, with constraints on factors such as general instability, buckling of shell between stiffeners, plate yielding, stiffeners yielding and operating depth. The shell thickness, the radii of the ellipse, the stiffeners offsets and the stiffeners dimensions are selected as design variables. Additionally, a sensitivity analysis is performed to study the influence of the design variables on the structural optimum design, the buoyancy factor，strength and stability．The Optimization results of this study provide a valuable reference for designers of underwater vehicles.