For improving the amphibious landing operations efficiency assessment, and enhancing ability to accomplish tasks of naval marine corps, use index method to evaluate the operation efficiency assessment of naval marine corps under sea battle environment. Analyze the naval marine corps weapon operation index system , according to characteristics of sea battle environment, put forward the calculation method of weapon operation efficiency assessment, then separately calculate the attack ability, motorized ability, protection ability and command communication ability of the main weapon, can carry out calculation analysis by the amphibious landing operation test data. The results show that the operation efficiency index which is calculated by the method is equal to the real situation, and the method can be used in marine weapon operation using and battle simulation system