In mobile communication systems, the intermodulation interference caused by the non-linearity of passive components may have a greater impact on the performance of networks, especially in a scene of multi-system combiners or sites deployed adjacent to each other. In this paper, we comprehensively analysis all the intermodulation interference may face by coexistence of multiple systems based on the third-order, the fifth-order and the seventh-order of passive intermodulation characteristics and with the frequency band of mobile communication systems for all mobile communication operators, which provide important reference for network design and construction.