The invention belongs to the technical field of signal filtering, and provides a wide stop band suppression filtering device. The filtering device is provided with an integrated monolithic structure by packaging a band-pass filter and two symmetrically arranged low pass filters in a ceramic matrix, and the band-pass filter is located at the middle position. The symmetrical low pass filters are added at the input end and the output end of the band-pass filter to achieve wide stop band higher harmonic suppression, and meanwhile the volume of the filtering device is reduced by reasonable arrangement of wiring; and meanwhile the filtering device is provided with the integrated monolithic structure by adopting the LTCC technique, so that the reliability is relatively high, and the problems of large volume and low reliability of the filtering device in the existing signal filtering technology are solved.