The Stiffness Solenoid Valve (SSV) is a critical actuator in Hydro-Pneumatic Suspension (HPS) systems. Its dynamic response characteristics directly dictate the regulation speed of the hydro-pneumatic spring stiffness, while the armature impact velocity and steady-state power consumption serve as vital indicators of the SSV‘s operational quality and reliability. In this study, the static and dynamic characteristics of the SSV under steady-state and transient conditions are systematically investigated using Maxwell electromagnetic simulation software. The static analysis reveals the influence of air gap length on electromagnetic force, while the dynamic study elucidates the intrinsic mechanisms governing the entire opening and closing process of the armature, providing a theoretical foundation for the design of high-performance solenoid valves. Furthermore, the effects of key parameters-including enameled wire diameter, magnetic isolation ring length, pole shoe height, and pole shoe top diameter-on impact velocity, steady-state power consumption, and dynamic response are examined in detail. On this basis, a multi-objective performance optimization method is proposed, integrating the Analytic Hierarchy Process (AHP) with Orthogonal Design. By quantifying engineering expertise into decision weights, this method achieves systematic parameter optimization under conflicting objective conditions. This research provides a method for the multi-objective optimization design of solenoid valves and even similar electromechanical products.