Objective: To investigate the outcomes of internal limiting membrane (ILM) peeling using microperimetry (MP) and multifocal electroretinogram (mfERG) instruments. Material and Methods: Forty-two eyes of 42 patients with ILM peeling were evaluated. Unity of outer stratums was assessed using spectral-domain optic coherence tomography. MfERG parameters (N1 and P1 amplitude, implicit time) and MP parameters were also measured both at baseline and month-12. Results: The mean P1 amplitude in ring 1 increased according to the baseline value (p = 0.002). However, the mean P1 amplitudes were lower compared with baseline values in mfERG in rings 2, 3, 4, and 5 (p = 0.016 for ring 2 and p < 0.001 for other rings). According to the preoperative retinal sensitivity of each of 37-point in MP, there was a reduction of 22.1% at month-12 in the ILM peeling area, and absolute microscotomas were detected in two points of two eyes at month-12. Metamorphopsia was associated with disrupted ellipsoid zone at month-12 (OR = 6.75, p = 0.008). Conclusion: The potential risk of a decrease in postoperative macular sensitivity should be taken into consideration if ILM peeling is planned in macular hole surgery.