Objective To compare the efficacy of extended pelvic lymph node dissection (ePLND) and standard pelvic lymph node dissection (sPLND) in open radical cystectomy.Methods We retrospectively analyzed the clinical data of 139 patients with bladder cancer cases in our hospital from January 2007 to January 2017,who underwent open radical cystectomy and pelvic lymph node dissection performed by the same group of surgeons.There were 117 males and 22 females,aged from 20 to 84 years old,with an average of (64.6 ± 11.7) years,91 patients were underwent ePLND group and 48 patients were underwent sPLND group.The preoperative anemia-free patients was compared between the ePLND group and the sPLND group [24 (50.0％)] vs.58 (54.9％),respectively],the patients with anemia were [24 (50.0％) vs.41 (45.1％)].The range of ePLND is:sway to the common iliac artery and the lower aortic (unreaching the inferior mesenteric artery);the lateral boundary to the reproductive femoral nerve;the distal end of the iliac artery at the groin level,the posterior border to the iliac vessels and closure,which contains the anterior tibial lymph nodes between the two sides.The range of sPLND is below the level of the common iliac artery bifurcation,and the rest of the range is the same as ePLND.The average operative time,average intraoperative blood loss,intraoperative blood transfusion,intraoperative and postoperative complications,postoperative eating time,postoperative activity time,postoperative exhaust time,postoperative hospital stay,mean gastric tube indwelling time,average pelvic drainage tube indwelling time,lymph nodes positive rate,lymph node density,and cancer-free survival were evaluated.Results All 139 patients underwent surgery successfully.The average operative time in the ePLND group and the sPLND group were [(351.2 ±79.5)min vs.(342.5 ± 69.3) min],average intraoperative blood loss [(314.6 ± 120.6) ml vs.(298.3 ± 126.3)ml],intraoperative blood transfusion [(702.9 ± 645.7) ml vs.(936.9 ± 818.1) ml],no intraoperative complications,postoperative complications [29 cases (31.9 ％) vs.18 cases (37.5 ％)],postoperative eating time [(5.4 ± 1.9) d vs.(4.8 ± 2.1) d],postoperative activity time [(2.1 ± 0.9) d vs.(1.9 ± 0.8) d],postoperative exhaust time [(3.8 ± 0.9) d vs.(3.6 ± 1.0) d],postoperative hospital stay [(14.9 ± 7.8) d vs.(15.5 ± 6.9) d],average gastric tube indwelling time [(4.8 ± 2.6) d vs.(4.53 ± 1.9) d],average pelvic drainage tube indwelling time [(11.1 ± 4.9) d vs.(10.9 ± 4.9) d],the difference was not statistically significant (P ＞ 0.05).A total of 2 359 lymph nodes were dissected from the two groups.The number of lymph nodes dissected in each of the ePLND group and the sPLND group was [(20.3 ± 3.8) vs.(10.6 ± 3.1),P ＜ 0.01],and the average number of positive lymph nodes was [(0.6 ± 1.3) vs.(0.3 ±1.0),P =0.034],the ratio of lymph node positive patients was [33 (36.3％) vs.9 (18.8％),P =0.026],and the lymph node density was [7.9％ (146/1848) vs.4.1％ (21/511)],the difference was statistically significant (P ＜ 0.05).In regard to prognosis,the disease-free survival rate (DFS) of ePLND group was 94.5％,91.0％,84.4％,81.1％,75.3％ at 1,2,3,4 and 5 years follow-up respectively.The other group was 70.5％,63.5％,57.8％,51.4％,41.1％ respectively.DFS of ePLND group tended to be higher than that of sPLND group in lymph node positive subgroups.The difference between the two groups was statistically significant (P ＜ 0.001).Conclusions In open radical cystectomy,ePLND and sPLND have similar surgical safety,but expanded lymph node dissection can improve disease-free survival in patients and improve the prognosis by increasing the detection range of positive lymph nodes.