Purpose : The purpose of this study is to assess the efficacy of enteroclysis through the previously insertedMiller-Abbott (M-A) tube for decompression in the postoperative intestinal obstruction. Materials & Methods : Thisstudy includes twenty patients who had intestinal obstruction symptoms after operation for benign(12) ormalignant(8) abdominal lesions. Small amount of barium was introduced to M-A tube for enteroclysis. We evaluatedthe presence, level, degree, and causes of obstruction on enteroclysis, compared with surgical(11) and clinical(9)findings. Results : Obstruction was seen in 18 cases including the two cases in which the level of obstruction wasnot clear. There was no obstruction in two cases. Obstruction on enteroclysis was demonstrated in all 11 operatedcases(100% accuracy, 1111). The level of obstruction on enteroclysis were jejunum in three cases, ileum in seven,and colon in one case. The levels of obstruction on enteroclysis were matched with those in operation field in 10cases. There were two cases of nonobstruction, nine cases of low-grade partial obstruction, and nine cases ofhigh-grade partial obstruction. We analyzed the findings on enteroclysis regarding causes of obstruction in 16patients with the findings of adhesive bands of extrinsic cause(9), cancer recurrence of intrinsic cause(6), andbezoar of intraluminal cause(1). Misinterpreted cases were two cases(87.7% accuracy, 14/16). The cause, fornonvisualization of obstruction site on enteroclysis in four patients included technical failure such asinadequate location of tube(1) and bowel overlapping(1), minimal obstruction(1), and nonexistent obstruction(1),in spite of diffuse edematous mucosa. Conclusion : Enteroclysis through the M-A tube for decompression in patientswith postoperative intestinal obstruction is an useful method for evaluation of intestinal obstruction.