Objective To identify the characteristics of and evaluate surgical impact on idiopathic macular hole (IMH) by using an optical coherence tomography (OCT) scanner. Methods Sixty-five cases (70 eyes) experiencing IMH were examined using OCT, then graded by their clinical characteristics. Nineteen cases (19 eyes) were scanned and measured using OCT before and after surgery. Results Of the 70 eyes, the number of stage I-IV macular holes were 11, 12, 36 and 11, respectively. For stage I holes, the OCT images revealed flattened or nonexistent fovea and minimally reflective space within or beneath the neurosensory retina; stage Ⅱ holes appeared to be full-sized with attached operculum and surrounding edema; stage Ⅲ holes were also full-sized with surrounding edema; finally, stage IV holes were full-sized and completely separated the posterior hyaloid membrane from the retina. Through quantitative measurements, OCT determined that the values for mean hole diameter, mean halo diameter and mean thickness of the hole's edge were reduced from 570.95±265.59 to 337.05±335.95μm, 1043.53±278.8 to 695.00±483.00μm and 389.78±60.58 to 298.78±109.80μm, respectively in 19 IMH cases after surgery. In 17 eyes, the holes or halos eventually closed or were reduced in size, or the edges of the holes thinned out. The anatomic successful rate of the surgery was 89%. Conclusion OCT can exhibit the characteristics of IMH and measure the diameter of holes quantitatively. This method can also judge the surgical impacts of IMH objectively, accurately and effectively.