Abstract: Objective To investigate indication of endopyelotomy to ureteropelvic junction obstruction(UPJO). Methods From Match 2007 to Match 2011, endopyelotomy was performed to 23 patients and dismembered pyeloplasty to 29 patients. We try to investigate indication of endopyelotomy by comparing success rates of the two procedures. Results The success rate of endopyelotomy was lower than that of pyeloplasty in UPJO patients with unfavorable features including severe hydronephrosis, crossing vessel ,long narrowed segment of ureteopelvic junction(>2 cm )and small calibrate double-J stent inserted in operation , the difference between two group was statistically significant（P<0.01）,while the difference was not statistically significant in patients without those features. Conclusions Endopyelotomy is indicated to UPJO patients with features including moderate hydronephrosis, no crossing vessel, short narrowed segment and fail pyeloplasty ,and large calibrate double-J stent should be inserted in operation.

Key words: ureteric-pelvic junction obstration（UPJO）, endopyelotomy, pyeloplasty