Abstract: Objective:To evaluate the clinical effects of bladder instillation with mitomycin C(MMC)and pirarubicin on preventing the postoperative recurrence of superficial bladder cancer.Methods:A total of 126 patients with superficial bladder cancer were randomly divided into MMC and pirarubicin group.The MMC group were treated with 30 mg of MMC and 30 ml of 0.9% sodium chloride injection through bladder instillation for 2 hours.The pirarubicin group were treated with 30 mg of pirarubicin and 30 ml of 5% glucose injection through bladder instillation for 30 minutes.The safety and postoperative recurrence of superficial bladder cancer in two groups were observed.Results:All patients were followed up for 24 months.The recurrence rates of MMC and pirarubicin group were 14.3% and 13.7%,the difference of which had no statistical significance and the tumour progression of two groups had no statistical significance(P0.05).The incidence rates of chemical cystitis in MMC and pirarubicin group were 32.0% and 38.5%,the difference of which had no statistical significance(P0.05).The adverse drug reactions of two groups were not obvious.Conclusions:The clinical effects of bladder instillation with MMC and pirarubicin on preventing the postoperative recurrence of superficial bladder cancer are similar.These two drugs can be used as the preferred drug for clinical bladder instillation.