With the increase of the number of antennas applied in the mobile platform, the electromagnetic compatibility problems of cars are becoming more and more serious. According to current situation of antenna layout lacking reasonable model and theoretical method, Matlab is used to control HFSS to generate different models for simulating and optimizing electromagnetic compatibility of the antenna layout by HFSS-Matlab-Api Script library. Using genetic algorithm to optimize layout. This approach can save mathematical model derivation process and reduce the work users repeatedly draw model and modify parameters of duplication. This approach can make full use of the simulation precision, reliability and convenience of HFSS, and using genetic algorithm to reduce the time and cost of blind test. In the end, the experimental results are consistent with the theory, thus verifying the feasibility of layout and optimization method.