Abstract: Objective:To analysis the characters of idiopathic epiretinal macular membrane（IERMM） pre-and post-operation by optical coherence tomography（OCT） and investigate the evaluation of OCT on surgery efficacy.Methods: 38 eyes of 38 cases of IERMM patients were performed vitrectomy combined with epimacular membrane peeling.The visual acuity,fundus color photograph and OCT images were noted pre-and post-operatively.Results: Preoperatively,the OCT characters of epiretinal membrane displayed as high-reflex strip in the inner surface of retina,varied in thickness and tightly adhered or partly bound to the surface or macula.The macular foveola got thickened in most patients and vision decreased.After operation,the abnormal reflex strip in the surface of retina disappeared,and the normal curve of macula recovered to normal or almost recovered to normal,with improvement in vision.In some cases,the macula were still edematous or damaged in pigment epithelium.Conclusion:The morphological characters of macular along with membrane could be disclosed by OCT so as to providing dependable messages for differential diagnosis,surgical indication and efficacy evaluation to IERMM.