Objective To detect the expression of SOX9 in urinary bladder carcinoma and explore its possible role in the occurrence and development of urinary bladder carcinoma.Methods Pathological samples of 80 patients who received surgery due to urinary bladder carcinoma in the Urinary Surgery Department of Huadou People'S Hospital were collected for the study.Carcinoma tissues from 60 cases were used as the research group,and benign tissues from another 20 cases were used as the control group.The expressions level of SOX9 were detected in the research subjects of the 2 groups by using immunohistochemistry (IHC) and Western blot (WB).Results Positive immunostainings of SOX9 were observed in the nucleus of carcinoma cells,while the SOX9 positive immunostainings in benign tissues could be noticed in the cytoplasm and nucleus of the surrounding gland epithelial cells.The expression level of SOX9 in bladder carcinoma was higher as compared with that of the benign tissue surrounding carcinoma,and the expression level of SOX9 in bladder carcinoma was higher than that of the benign tissues surrounding carcinoma.Statistical significance could be seen in the expression level of SOX9,when comparisons were made between carcinoma tissue and non-carcinoma tissue(P ＜ 0.001).However,clinical pathological grading seemed to have no association with age and gender(P ＞ 0.05).Conclusion The expression level of SOX9 elevated in bladder carcinoma,and significant differences could be seen in the expressed levels of carcinoma and benign tissues,which might be a potential biomarker in the diagnosis of bladder carcinoma.