Purpose: To determine the efficacy of a novel technique for a ‘transconjunctival 20-gauge vitrectomy’ (T20V). Methods: In total, 12 eyes of 12 consecutive patients were included in a prospective study. The mean age was 58 years (range: 38–74 years); 4 patients were male and 8 were female. The T20V was indicated when short-duration vitrectomy was envisioned: macular surgery for macular hole and epiretinal membrane therapy, moderate vitreous hemorrhage due to retina vein occlusions or diabetic retinopathy, or neurotomy for central retinal vein occlusion. Results: The average time for each procedure was 35 ± 30 min (SD). The preoperative visual acuity ranged from 20/200 to hand motions, while postoperative vision was between 20/30 and counting fingers. The average intraocular pressure changed from 16.1 ± 5.6 mm Hg preoperatively to 15.8 ± 8.1 mm Hg in the first postoperative day, and 17.8 ± 9.4 mm Hg 1 week after surgery – these differences were not statistically significant (p > 0.05). Subjective postoperative pain and foreign body sensation at postoperative day 1 and week 1 were mild to moderate. The chemosis observed 1 h after surgery was minimal, and disappeared quickly during the 1-week follow-up. Conclusion: The T20V is suitable to perform short-duration vitrectomy surgery, and has a low rate of ocular complications, similar to 25- or 23-gauge sutureless vitrectomy systems.