Objective To investigate the diagnosis and treatment of bladder dysfunction after radical resection of rectal carcinoma.Methods One hundred and sixty-five patients with bladder dysfunction after radical resection of rectal carcinoma were observed by urodynamic study.The results included maximum urinary flow rate,postvoid residual,urine volume,pressure of detrusor,maximum urethral closure pressure.These patients were treated by different methods.Results Bladder with underactive detrusor were 116 patients,109 patients returned to normal voiding after 3 months,7 patients were performed with suprapubic cystostomy.Detrusor overactivity were 42 patients,insufficiency of urethral sphincter were 7 patients,all symptoms of them improved after treatment.Conclusion Patients with bladder dysfunction after radical resection of rectal carcinoma should do check to clear etiology,according to the results to take the appropriate means to treatment.