Abstract: Objective To study the expression of Gli1 protein,a component of Hedgehog/Gli1 signal pathway,and its relationship with angiogenesis in human breast cancer. Methods The expression of Gli1 protein was investigated by immunohistohistochemical method in 79 cases of human breast cancer,68 cases of normal tissues adjacent to cancer and 42 cases of breast fibroadenoma tissues.The microvascular density(MVD) was examined by using immunohistochemical CD34 staining assay. Results The Gli1 expression was higher in breast carcinoma than that in adjacent normal tissues and in breast fibroadenoma(P<0.05).Expression of Gli1 was significant higher in TNM stage Ⅲ than that in TNM stageⅠ～Ⅱ(P<0.05) and also was higher with axillary lymphnode metastasis than without lymphnode metastasis(P<0.05).Expressions of Gli1 were positively correlated with MVD(r=0.325，P<0.05). Conclusion Gli1 protein is activated and plays an important role in development of breast cancer.Promoting angiogenesis might be one of its mechanisms.