Objective To confirm the expression of BTG1 in renal clear cell carcinoma (RCCC) and its role in 786-O cells proliferation and apoptosis in vitro. Methods The expression of BTG1 in 20 RCCC specimens was examined by immunohistochemical staining and its role in cell proliferation and apoptosis were performed with MTT and Hoechst respectively. Results Immunohistochemistry of normal and malignant kidney tissue sections of 20 patients demonstrated positive BTG1 staining for 85% (17/20) of RCCC, compared to 25% (5/20) of normal adjacent tissue (P < 0.05). We also found that overexpression BTG1 in 786-O cells reduced their proliferation but induced their apoptosis, while knockdown BTG1 in 786-O cells increased their proliferation but reduced their apoptosis (P < 0.05). Conclusion BTG1 may be involved in RCCC carcinogenesis.