Abstract: Objective:To evaluate the effects and safety of deep lateral orbital decompression in the treatment of thyroid-associated ophthalmopathy(TAO).Methods:The clinical data of patients with TAO treated with deep lateral orbital decompression from January 2016 to January 2018 were collected.The proptosis,best corrected visual acuity(BCVA),intraocular pressure(IOP),distance of upper and lower lid margin from reflex(MRD-1 and MRD-2,respectively),diplopia and ocular restriction between before operation and after 3 months of operation were compared.Results:The mean age of 23 patients with thirty-five orbits9 male(12 orbits),14 female(23 orbits) was(41.5±14.4)years.The average proptosis reduction was(3.7±0.9)mm(P<0.01).The mean IOP reduction was(1.9±1.6)mmHg(P<0.01).The median improvement in upper and lower eyelid retraction were 1.0 mm(P<0.01).After operation,the diplopia in two cases worsened,the diplopia in 3 cases relieved,the ocular dyscinesia in 6 cases relieved,and no aggravation was found.Conclusions:Deep lateral wall orbital decompression can effectively expand orbital volume,and improve eyelid retraction.The eye clearly recedes,the incidence rate of postoperative diplopia is low,the visual recovery is good,and the intra-orbital injury is little.