【Abstract】Objective: To investigate the expression of TGF-β axis in giant cell tumor of bone. METHODS: Twenty-seven patients with giant cell tumor of bone treated from May 2016 to December 2018 were enrolled. All patients were diagnosed by pathological examination. All patients underwent surgical treatment. The lesions and adjacent tissues were taken during surgery. Distance lesion tissue > 3 cm). The expression of TGF-β axis in different lesions was determined by immunohistochemistry. The pathological data were used to record the age, sex, tumor size, imaging stage, pathological grade, recurrence, presence of tissue infiltration, and tumor of giant cell tumor. The TGF-β axis expression levels under different pathological conditions were analyzed. The factors of TGF-β axis were analyzed by multivariate logistic analysis. RESULTS: The positive rate of TGF-β-axis protein in the lesions of osteoblastoma was higher than that in adjacent tissues (P<0.05). The results of immunohistochemistry showed that TGF-β-axis protein was mainly localized in mononuclear interstitial cells in osteoblasts, and localized in the nucleus, while the expression level in adjacent tissues was low or not. The logistic analysis showed that: The positive rate of TGF-β axis expression in tumor tissues of osteoblastoma was statistically significant (P<0.05) in tumor diameter, imaging staging, pathological grade, recurrence, and presence of tissue infiltration. Conclusion: The TGF-β axis is highly expressed in osteoblastoma tissues, and the expression level is affected by many factors, which can reflect the severity of the disease. Strengthening its level can evaluate the prognosis and guide clinical treatment.