The system of combat vehicle consists of a drive system including car body, suspension system, powertrain system, and maneuvering system and a firing system including barrel, turret, and ammunition. Since there are many components which make up each system that various simulation scenarios must be performed due to the characteristics of the combat vehicle. It is necessary to perform batch job which is link simulation software and optimization software to design optimization using the simulation model. However, it takes a lot of time to analyze the simulation model and to set up input and output of simulation model by using MATLAB software. Also, optimization time can be increased due to the calculation of numerical differentiation. In this research, integrated interface is constructed through Maple software of Maplesoft corporation to design optimization of the combat vehicle which is built with MapleSim simulation software of Maplesoft. The design optimization of combat vehicle is performed by using the integrated interface which consists of analysis of variance (ANOVA), design of experiment (DoE), construction of kriging surrogate model and optimization. In addition, the response of the surrogate model is expressed as a mathematical expression and the sensitivities calculated by symbolic computation are used to reduce the optimization time.