A film bulk acoustic wave resonator(FBAR) filter operating at 2, 4 GHz WiFi band (2 401~2 483 MHz) is designed in this paper, This design is a ladder filter based on the one-dimensional Mason circuit model of FBAR, which is built in ADS,the finite element electromagnetic model of packaging structure and test circuit is established in HFSS,and the joint simulation design is completed in ADS, Through MEMS process preparation and test,the insertion loss of the filter at 2 401~2 483 MHz frequency band, the insertion loss is ≤2, 2 dB,the out of band rejection at 2 520~2 900 MHz is ≥40 dB,and the volume of the filter is only 1, 1 mm×0, 9 mm×0, 65 mm,