Goniotomy using Nd-YAG laser was carried out in 8 eyes of 6 cases with juvenile primary developmental glaucoma, in one eye with primary congenital glaucoma, in one eye with Axenfeld's anomaly and in one eye with Sturge-Weber syndrome. The chamber angles of these eyes showed various degrees of trabeculodysgenesis, and the laser shots placed anterior to the end of the iris insertion separated the iris tissue from the trabecular band. The angle circumference over 3 to 8.5 hours with an average of 4.8 hours could be treated by one session of the laser treatment in 8 eyes and by two sessions in 3 eyes. In cases with juvenile primary developmental glaucoma, the intraocular pressure (IOP) could be controlled below 20 mmHg with antiglaucomatous medication in 5 eyes by one session and in 2 eyes by two sessions of the laser treatment, but the IOP was not controlled in one eye. In the eye with primary congenital glaucoma aged 41 years and the eye with Sturge-Weber syndrome, the treatment failed to control the IOP. In the eye with Axenfeld's anomaly, the IOP was controlled with reduced medication. The postoperative complications embraced iritis, anterior chamber hemorrhage and IOP rise, but they left no serious consequences. Nd-YAG laser goniotomy may be useful for the treatment of juvenile primary developmental glaucoma.