Aiming at the problems such as structural instability, fatigue failure and shortened service life of submarine cable in suspension section, based on the vortex-induced vibration mechanism of submarine cable under ocean current and combined with the structural characteristics of submarine cable, a vibration simulation model suitable for submarine cable is established by using the hydrodynamic method. Based on the simulation calculation model for studying the characteristics of current velocity, cable machinery (cross section, quality, since the damping characteristics, etc.) dangling off length of cable vibration and fatigue damage and the effect of combination should be modified fatigue curve and rain flow count method, calculation of submarine cable fatigue damage, according to the linear accumulated damage theory to get the fatigue life of submarine cable, Analysis the influence factors of the fatigue life of submarine cable, the results showed that the increased by submarine cable elastic modulus and damping ratio, shorten the cable dangling length can effectively extend the fatigue life of submarine cable.