The therapy-related morbidity was evaluated in 121 patients with muscle-invasive or recurrent superficial bladder cancer treated with radiotherapy and cystectomy. In 103 patients cystectomy succeeded 39-52 Gray (Gy) preoperative irradiation and in 18 patients cystectomy was done as a salvage procedure after previous full-dose radiotherapy. The overall frequency of complications was high; 71% of the patients treated with preoperative and 78% treated with full-dose radiotherapy had clinically relevant complications related to radiotherapy or surgery or both. The rate of intestinal complications was 39% for preoperative and 67% for full-dose radiotherapy. The overall mortality rate in intestinal complications was 3.3%. This study shows that the combination of radiotherapy and radical surgery in patients with bladder cancer is associated with a high rate of intestinal complications. The complications are significantly related to the irradiation dose and are long lasting and even life threatening.