Heavy missile launchers mostly use 4-axles linked dual-chamber HPS(hydropneumatic suspension), in order to study their linkage coupling effect for the reference of launcher design. The simulation models of an interconnected HPS of two-axles and four-axles were built based on the mathematic model and AMESim software. Based on this, the influence of the coupling effect of the multi-axles connected twin-accumulator HPS system was analyzed under several different excitation frequencies. The results show that even under low-frequency excitation, the multi-axis interconnected HPS has obvious damping characteristics. Compared with the two-axles interconnected HPS system, the external characteristics of the four-axles interconnected HPS system have advantages. The external characteristics of the connected HPS system are more intense when excited by low frequency and good when excited by high frequency, indicating that the system can attenuate the asynchronous vibration of the system when it is in a high frequency environment.