This paper focuses on the design of RF filtering front-end module. In view of the RF signal transmission and isolation problems involved in the miniaturized and highly integrated design of the module, a refined three-dimensional electromagnetic field modeling simulation analysis is carried out to improve the model accuracy. In order to verify the simulation design accuracy, the key structural model are fabricated and de-embedding tested.And an L-band miniaturized RF filtering front-end module has been fabricated. The module size is 14.97 mm×12.01 mm×1.29 mm. The number of the integrated filters is 16. The insertion loss is ≤5.2 dB, and the out-of-band rejection is ≥42.5 dB.