There are many components and complex structure relationships in weapon system.The ability model can be reduced and optimized by effectively judging the weight of the relationship, and the computational complexity of the subsequent simulation evaluation can be effectively reduced by reducing the complexity of the model.In order to solve this problem, nonlinear thinking is introduced into the theory of structural equation modeling (SEM). Considering the factors of synergy and secondary effects between capability subjects, a method for solving the relationship between combat capabilities based on nonlinear SEM is proposed.Finally, taking the tactical information distribution capability as an example, the effectiveness of the method is verified by comparing the evaluation results of linear and nonlinear SEM.