Objectives: To evaluate the changes of retinal nerve fibre layer (RNFL) and ganglion cell layer/inner plexiform layer (GCL/IPL) with the severity of thyroid eye disease (TED).Methods: One hundred and forty-five eyes of 75 patients with TED and 70 eyes of 35 healthy controls were included. The eyes with TED were divided into mild group (35 eyes), moderate-to-severe group (42 eyes) and DON group (68 eyes).