Objective To evaluate the long-term result of vitrectomy for macular epiretinal membranes(ERM) and the relationship between bestcorrected visual acuity(VA) and macular thickness. Methods In a retrospective consecutive series, twenty-two eyes(17eyes of idiopathic（77％） and 5 of secondary ERM（23％）) of 2 2 patients with macular ERM who underwent pars plana vitrectomy and membrane peeling which had more than 1 yearprime;s (12.40 months，mean(23plusmn;8)months)follow up were included. All the patients were examined by VA, fundus color photography, fluo rescein fundus angiography (FFA) optical coherence tomography (OCT) before and after treatment. VA was adopted 5 points record; FFA and OCT were underway as common way. The mean of VA was (4.25plusmn;0.36), the mean of macular thickness was (4.99 plusmn;114) mu;m. Compared the VA, appearance of fundus photography, fluorescein angio graphy and optical coherence tomography (OCT) before and after surgery. Results Visual improvement was achieved in 13 eyes (59%), meanwhile, 6 eyes (27%) were s table and 3 eyes (14%) were worse; VA of 15 eyes (66%) was more than 4.5 at last follow-up. The mean VA increased from (4.25plusmn;0.36) to (457plusmn;031) postope rative ly, the difference was statistically significant (P＜0.05). Mean macular thi cknes s decreased from (499plusmn;114) mu;m (317-774 mu;m) to (286plusmn;104) mu;m (150-597 mu;m) (P＜0.05) postoperatively, the difference was statistically significant (P＜0.05), but still different to the opposite eyesprime;((184plusmn;37) mu;m)(P＜0.05).VA correlated with macular thickness preoperatively (r=-0.64,P=0.001)and postoperat ively(r=-0.58, P=0.01) except the patients with cataract improvement without therapy. 6 eyes(27%) had retinal hemorrhage and 2 eyes(9%) had peripheral retinal breaks intraoperati vely; 5 eyes(23%) had secondary higher intraocular pressure, 1 eye(5%) had macul a hole and 8 eyes(36%) had cataract improvement postoperatively. Conclusions Surgery is successful in treating ERM. It can relieve macular edema and improve visual acuity. （Chin J Ocul Fundus Dis，2008，24：206-209）