Balloon dilatation of nasolacrimal drainage apparatus was attempted for the treatment of stenoses or obstructions of the nasolacrimal system in 49 eyes of 41 consecutive patients with complete obstructions and 16 eyes of 14 patients with incomplete obstructions. These two groups were compared with regards to the effectiveness of balloon dacryocystoplasty. All patients suffered from severe epiphora had already undergone multiple probings. A 0.018-inch hair or ball guide wire was introduced through the superior punctum into the inferior meatus of the nasal cavity and pulled out through the nasal aperture using a hemostat under nasal endoscopy. A deflated angioplasty balloon catheter was then introduced in a retrograde direction and dilated under fluoroscopic control. No major complications occurred in any of the patients. At 7 days after balloon dilatation, 25 of 49 eyes with complete obstruction demonstrated improvement in epiphora (initial success rate : 51.0%) and among them 17 eyes showed complete resolution of symptoms. Reocclusion occurred in 12 of the 25 eyes with initial improvement at the 2-months follow up. For the 16 eyes with incomplete obstruction, and improvement of epiphora was attained in 11 eyes (initial success rate 68.8%): 5 fo these eyes showed complete resolution of epiphora, and 3 was failed to maintain initial improvement at the 2-months follow up. Although this study demonstrates that results of balloon dacryocystoplasty are not enocurging because of the high failure and recurrence rate, balloon dacryocystoplasty is a simple and safe nonsurgical technique that can be used to treat for obstructions of the nasolacrimal system. In addition, balloon dacryocystoplasty shows better results in incomplete obstruction than in incomplete obstruction than in complete obstruction of the nasolacrimal system.