AIM: To analyze the application value of spectral domain-optical coherence tomography(SD-OCT)parameters on evaluating visual acuity improvement after internal limiting membrane peeling of macular hole.METHODS: The retrospective analysis was performed on the clinical data of 82 patients(82 eyes)with idiopathic macular hole(IMH)who underwent vitrectomy + internal limiting membrane peeling + long-acting gas tamponade in the hospital between May 2019 and February 2021. The correlation between IMH closure and SD-OCT parameters at 3mo after surgery was analyzed, and the risk factors for poor postoperative visual acuity improvement were evaluated.RESULTS: Spearman rank correlation coefficient analysis showed that IMH closure at 3mo after operation was positively correlated with preoperative external limiting membrane(ELM)defect diameter(rs=0.308, P<0.05), and it was negatively correlated with preoperative macular hole index(MHI; rs=-0.266, P<0.05). Logistic regression analysis revealed that preoperative MHI≥0.5 was a protective factor affecting poor postoperative visual acuity improvement(OR=0.691, P<0.05).CONCLUSION: SD-OCT can predict the surgical efficacy by detecting the preoperative MHI and ELM defect diameter, and it is beneficial to judging the improvement of visual function.