We retrospectively analyzed early postoperative complications in 293 consecutive patients withbladder cancer who underwent radical cystectomy with urinary diversion from 1990 to 2007 at the Department of Urology of the Sapporo Medical University School of Medicine. The Common Terminology Criteria for Adverse Events (ver 3.0) was used to evaluate complications that occurred within 30 days after surgery, and grade 3 and higher grades according to the criteria were defined as complications in this study. The guidelines of the Centers for Disease Control and Prevention were used for the classification of surgical site infection. Early postoperative complications were found in 158 cases (54%). Acute pyelonephritis (APN), which was related to the removal of the ureteral catheter, was the most frequent complication, found in 96 (33%), followed by surgical site infection in 39 (13%), and ileus in 33 (11%). When transient APN was excluded, the rate for complications was 30%. Possible life-threatening complications were experienced in 15 patients (5%) including 2 (0.7%) who eventually died of the complications. The preoperative grade 3 score of the American Society of Anesthesiologists (ASA score) was significantly related to development of early postoperative complications in univariate analysis. In multivariate analysis, a grade 3 ASA score and the estimated blood loss were independent factors to predict development of early complications. Postoperative nasogastric tubing was not related to ileus after surgery, suggesting that postoperative indwelling of the tube is not routinely needed. Although about half of the patients experienced early postoperative complications, they were usually transient and manageable. Thus, careful evaluation of the preoperative ASA score and a reduction in the amount of bleeding during surgery may lower the development of early postoperative complications.