The aim of this study was to assess the preliminary results and long term follow-up of the treatment of Hirschsprung's disease by Transanal pull-through approach once stage at National Hospital of Pediatrics. Methods: the authors analyzed the records of 75 patients. Among these were 59 boys (78.7 percent) and 16 girls (21.3 percent), ages ranging from 15 days to 36 months. Forty-four (44) patients had rectal aganglionosis (58.7 percent), 28 patients had recto-sigmoid aganglionosis (37.3 percent) and 3 patients had aganglionic segment to left colon (4.0 percent). Operative average time was 92 minutes. Results: There were 14 patients that required a combination of transanal pull-through and laparoscopy (2 patients) or Pfannenstiel (12 patients) approaches due to the shifted mesenteric artery of sigmoid colon (16.0 percent). The aganglionic segment was very long in the other, intra-operative bleeding and primary adhesion peritonitis. There was no death observed during and after operation. There was 1 anastomose bleeding which is stopped spontaneously and 2 infectious wounds. 75 patients could pass stool spontaneously before discharge. Conclusion: Transanal pull-through approach once stage can be performed safely to treat Hirschsprung's disease effectively.