Objective: Evaluate the results of laparoscopic transperitoneal treatment of the ureteropelvic junction obstruction at Viet Tiep Hospital. Materials and method: 54 patients with ureteropelvic junction obstruction underwent laparoscopic transperitoneal reconstruction from January 2009 to December 2010. Results: There were 41 male and 13 females, age from 01 to 79, 32 cases of ureteropelvic junction obstruction on the left and 22 cases on the right side. UIV revealed 70.4 percent kidney with severe hydronephrosis, which has 12.9 percent non-function kidney. The cause of ureteropelvic junction obstruction in chidren is usually caused by during fetal development, resulting in a narrowing of the ureteras it's forming, in adult common cause is due to abnormal blood vessels under the pole. The average operating time was 90 minutes (60 - 360 minutes). the authors perform the pyelography with placement double J in 24 percent, pyelography with placement Modelage through the skin in 76 percent. There wasn't any complications. The average length of hospitalization post surgery, 6 + or - 4 days. The result of the treatment in the long term is 84 percent good, 12 percent fair, and 4 percent bad. Conclusion: Ureteropelvic junction obstruction reconstruction by transperitoneal laparoscopy is feasible in the condition with encouraging postoperative outcome. It has become routine in the hospital.