The optimization of operational test indexes plays an important role in simplifying test subjects， saving test resources and shortening test cycle. For the coexistence of a large number of qualitative and quantitative indicators in the operational test system， an optimization method of operational test index based on rough set and genetic algorithm is proposed. Based on the initial frame of operational test index system， the decision information table of operational test index system is built， and its attributes are reduced by rough set and genetic algorithm to obtain a simplified index set. The method is verified by a fire operational effectiveness test case of anti-aircraft gun weapon.