Juvenile open-angle glaucoma patients with thick central corneas and negative family history were more likely to undergo surgery, mainly trabeculectomy with half requiring additional surgery within 10 years. To assess the characteristics and treatment outcomes of patients with juvenile open-angle glaucoma (JOAG) in Thailand. This retrospective, multicenter study included all patients diagnosed with JOAG over 12 years from two tertiary hospitals in Bangkok, Thailand. A total of 200 eyes from 104 patients were included in this study. The mean age of onset was 24.0±10.1 years (range 5-40), with male predominance (60.5%). Over 90% of patients had bilateral JOAG and 25% had a positive family history. Negative family history (AOR=4.59, P=0.02) and thick central corneal thickness (CCT) were surgical predictors (every 10 micron AOR=1.29, P=0.01). Over 70% of cases needed glaucoma surgery. Trabeculectomy with Mitomycin-C was performed on 131 eyes (65.5%) with a cumulative probability of complete success of 71.0%, 57.8%, 39.2%, and 26.9% and qualified success of 86.3%, 73.6%, 64.8%, and 45.7% at 1, 3, 5, and 10 years, respectively. Mean follow-up after surgery was 94.9 ± 69.8 months (range 13-153). There were no serious post-operative complications. Myopia and number of baseline glaucoma medications were significantly associated with surgical failure. Trabeculectomy with Mitomycin C was the most common primary surgery performed in Thai patients with JOAG, and successfully reduced intraocular pressure without significant complications. Patients with thicker corneas were more likely to undergo surgery. By 10 years, half of the patients required additional surgery and risk factors for failure included myopia and the number of medications.