Purpose: To compare histopathologic findings of patients who underwent transurethral resection of a bladder tumor (TUR-B) between groups with and without the metabolic syndrome. Materials and Methods: We retrospectively analyzed data of 535 patients who underwent TUR-B in our department between October 2005 and March 2011. All patients had primary urethelial cell carcinoma (UCB). Histologic stage, grade, the presence of hypertension, diabetes mellitus, body mass index (BMI), waist circumference, HDL and trigliseride levels were evaluated. The TNM classification was used, with Ta tumor accepted as lower stage and T1 and T2 tumors as higher stage bladder cancers. Also, the pathological grading adopted by the 2004 World Health Organization grading system were applied. Non-invasive papillary urothelial neoplasms of low malignant potential were regarded as low grade. Results: Among the total of 509 patients analyzed in our study, there were 439 males (86.2%) and 70 females (13.8%). Metabolic syndrome was significantly associated with high histologic grade, and high pathologic stage (p<0.001). Conclusions: The patients with metabolic syndrome were found to have statistically significant higher T stage and grade of bladder cancer. Further studies with more patients are needed to confirm our study.