Two novel low pass filters(LPFS) of wide stop band based on the structure of photonic band gap(PBG) and the structure of microstrip are proposed. The proposed filters were made of a PBG microstrip structure with T junction opened stubs and cross junction opened stubs, respectively. The transmission characteristics of the proposed filters were also discussed. The new LPFs are easy to design and fabricate. Finally, The simulated and experimental results verify the validity of the proposed LPFs.