Photonic crystal waveguide has the characteristics of high transmissio n rate,low loss rate and good stability,so it has a very broad application pro spect in optical integration,optical information transmission and other fields. However,as a sub-wavelength waveguide,there is a diffraction limit,the emit t ed light of the photonic crystal waveguide will diverge to all directions,affec ting the outgoing beam.In order to solve the problem of controlling the light f ield at the output end of the waveguide,this paper proposes a new type of two- d imensional square lattice photonic crystal beaming structure.This structure gre atly increases the radiation distance of the emitted light by introducing the sa wtooth structure and multi-branch channels on the surface of the outgoing end o f the waveguide.The analysis results using the finite difference time domain met hod show that the square lattice photonic crystal with 3sawtooth ports and 2br anches can achieve the best outgoing light bundle,and the radiation distance is up to 200μm,which is about 25times that of the single-wave derived projecto r structure.The radiation efficiency of this structure can reach 53% at 200μm.