We analyzed the long-term results of trabeculectomy operation in 100 eyes of 80 primary open angle glaucoma, patients followed up one to five years. Complete success was achieved 78 of cases (% 78). Reduce of intraocular pressure closely related to the presence of a filtering bleb. The main complication was the late appearance of lens opacities, although these seemed less frequent than the other antiglaucoma operations.