Objective To investigate the mechanism of Wenyang Tongluo Recipe against synovial neovascularization in mice with collagen-induced arthritis(CIA). Methods The mice with CIA were randomly divided into methotrexate group, model group, blank control group, Wenyang Tongluo Recipe of high, middle and low dose groups, with 5 mice in each group. Measuring toe volume, HE staining and the expressions of Ang-2 and VEGF in synovium were detected by immunohistochemistry and Western blot. Results There were no significant differences in toe volume of DBA/1 mice in each group before treatment(0 d) and on 35 d, while significant differences in toe volume when compared with the blank control group on 48 d(P<0.01). Compared with the model group, the blank group, methotrexate group, Wenyang Tongluo Recipe of high, middle and low dose groups had significant differences(P<0.01). There was no difference in methotrexate group and high dose group. HE staining of synovium tissues in model group showed a lot of lymphocyte infiltration and synovium proliferation, while methotrexate group, Wenyang Tongluo Recipe of high, middle and low dose groups showed only a small amount of lymphocyte, and no obvious synovium proliferation. There were a lot of Ang-2 and VEGF protein expressions in model group, and the expression levels of Ang-2 and VEGF decreased in methotrexate group, Wenyang Tongluo Recipe of high, middle and low dose groups (P<0.01). Western blot showed that the levels of Ang-2 and VEGF in blank group, methotrexate group, Wenyang Tongluo Recipe of high, middle and low dose groups were significantly lower than those in model group. Conclusion Wenyang Tongluo Recipe could prevent the formation of new blood vessels in synovium of collagen-induced arthritis mice, thus reduce synovitis.