Based on the definition of weapon system effectiveness and the ADC basic model given by WSEIAC,and aiming at the characteristics of operational use of LM AUV,this paper improves the basic functions of usability and credibility. The energy vector of system is obtained by using fuzzy level analysis method and multiplicative model. Then,the system efficiency evaluation model of LM AUV is established. Finally,the analysis of calculation results proves that this method can effectively evaluate the effectiveness of LM AUV system.