Objective To evaluate the therapeutic efficacy of endoscopic transnasal orbital decompression for dysthyroid optic neuropathy(DON). Methods The data of 45 eyes of 26 cases with DON underwent the endoscopic transnasal orbital decompression surgery between Feb.2012 and Nov.2015 were collected and analyzed retrospectively. The visual acuity, intraocular pressure, proptosis, diplopia, colour sense, visual field and eye movement before and after surgery were observed. The follow-up time was 12-24 months. Results The postoperative best corrected visual acuity was improved in 45 eyes(100.00%). The preoperative best corrected visual acuity was light sense to 0.4 in 42 eyes(93.33%). The postoperative best corrected visual acuity was 0.5-1.5 in 41 eyes (91.11%) .The difference in reduction of proptosis and intraocular pressure were statistically significant. New-onset diplopia or its aggravation was recorded in 6 cases(23.08%). No complication happened during the surgery. Conclusion Endoscopic transnasal orbital decompression is a safe and minimally invasive surgery for the treatment of DON without serious complications. Key words: Optic neuropathy, dysthyroid; Orbital decompression, endoscopic, transnasal