Inguinal hernia is a known complication after radical retropubic prostatectomy (RRP). We have investigated whether other types of lower midline incision surgery in males increase the risk of inguinal hernia. Male patients operated with open prostatectomy for benign prostate hyperplasia (n = 95), pelvic lymph node dissection for staging of prostate cancer (n = 88), or cystectomy for bladder cancer (n = 76) were identified and were sent questionnaires in which they were asked about postoperative inguinal hernia morbidity. Two-hundred and seventy-one men operated with RRP had previously received a similar questionnaire. The answers were compared with those from a control group of 953 men who had not undergone surgery. Annual attributional hernia morbidity and Kaplan-Meier hernia-free survival were calculated. The cumulative incidence of post-operative inguinal hernia and annual attributional hernia morbidity after the respective surgical procedures were clearly higher during the early years post-operation than for nonoperated patients. Inguinal hernia is a common postoperative complication in males after all the lower midline incision surgery investigated.