PURPOSE: To assess the efficacy and safety of a novel non-inverted, free single-layer internal limiting membrane (ILM) flap technique for treating large full-thickness macular holes (FTMHs). METHODS: Patients with FTMHs underwent a standard 3-port pars plana vitrectomy using the 23-gauge vitrectomy system. Unique to this technique, a "tongue-shaped" ILM flap was initially created, followed by the formation of two "handles" and the bottom of "plastic bag" ILM flaps. Under perfluoro-n-octane (PFO), the two-point fixed "plastic bag" ILM flap was transferred to the free flap and dragged to cover MH using the ocular viscoelastic device (OVD) to cover the margin of the ILM flap, followed by gas tamponade. Preoperative and postoperative assessments included best-corrected visual acuity (BCVA) and spectral domain optical coherence tomography (SD-OCT). RESULTS: The 13 patients (mean age 64.38 ± 8.08 years, macular diameter 664.85 ± 153.38μm) demonstrated a significant improvement in BCVA from 1.03 ± 0.22 logMAR preoperatively to 0.78 ± 0.26 logMAR postoperatively (P = 0.0004). In all cases, successful closure of the MH was accomplished, including 10 (76.92%) U-shaped closure, 1 (7.69%) flat closure, 1 (7.69%) W-shaped closure, 1 (7.69%) flap closure, with no ILM flap dislocations. CONCLUSIONS: The non-inverted single-layer "plastic bag" ILM flap technique has been demonstrated to be both a safe and effective method for managing large FTMHs, offering a promising alternative to traditional methods with improved anatomical restorations and stable visual outcomes.