ObjectiveTo evaluate nerve-sparing semi-cystectomy for bladder cancer at trigone or bladder neck.Methods6 patients suffering from multi and invasive cancer at trigone or bladder neck underwent semi-cystectomy and in 5 of which the nerve-sparing technique was carried out.The post-operative outcome was evaluated.ResultsAll patients were followed up for 9～36 months.With nerve sparing surgery,sexual function has been preserved in 4 of the 5.Radical cystectomy was performed for 1 case because of tumor relapse.Unilateral hydronephresis was noted in another one.ConclusionsQuality of life has been good and erectile function can be preserved by nerve-sparing technique.