Applying the antibody of CD34 stained the vascular endothelial cell of periodontal tissue and investigated the effects of He-Ne laser irradiation on the blood vessel remodeling (BVR) of orthodontic periodontal tissue in rabbit. 35 rabbits were divided into normal group and experimental group randomly. All of the tissue sections proceeded with CD34 immunohistochemical staining, measured the microvessel density (MVD) the microvessel area (MVA) of periodontal tissue by computer image analyzing system using SPSS software to proceed with statistic test. MVD and MVA received He-Ne laser irradiation were higher than those of the control side. The differences of MVD, MVA between the irradiated and control side in every experimental group were all significant (P<0.05, P<0.01), except for the 1st day group.