Second transurethral resection of bladder tumor (TUR-Bt) is a standard treatment for high grade T1 initial, non-muscle invasive bladder cancer. In our hospital from October 2008 to April 2017, 2nd TUR-Bt was performed in 51 cases of initial T1 bladder cancer. The risk factors of residual tumors on 2nd TUR-Bt and the clinical outcome were examined retrospectively. Twenty two of the 51 cases (43.1%) had residual tumors on 2nd TUR-Bt, and upstaging was not admitted. To determine the risk factor for residual tumors in 2nd TUR-Bt, we examined gender, tumor morphology (papillary/non-papillary, pedunculated/ nonpedunculated), number of tumors (single/frequent), and tumor size (≧20 mm/＜20 mm), but none of these were significant risk factors for tumor residue. The recurrence free survival (RFS) of the 51 cases was 86.0% after 1 year, and 77.0% after 3 years. There tended to be a higher RFS in the pedunculated tumor group, pT0 group on 2nd TUR-Bt, intravesical BCG therapy group, but no statistically significant difference was observed. The progression free survival (PFS) was 90.6% after 3 years, and 87.3% after 5 years. These values were similar to those reported previously.