Background: Hematogenous retinal detachment is just one of many surgical indications where the 27G system has been shown to be both safe and useful. Objective: This study aimed to compare the results of chandelier assisted 23, 25, 27 gauge bimanual vitrectomy in diabetic vitreous hemorrhage and diabetic tractional retinal detachment. Patients and Methods:There were a total of 30 eyes from 30 diabetic individuals in this prospective research of pars plana vitrectomy. The study was conducted throughout 18 months (January 2018 to June 2019) in two private eye centers in Alexandria (El-Safwa and Ebsar centers). Patients were divided into three groups according to the used vitrectomy system (10 eyes per group): Group (I, II & III), each included 10 patients underwent vitrectomy surgery using 23-gauge system, 25-gauge system and 27-gauge system respectively. Results: The 27 gauge group took the highest operative duration (40.2 ± 7.5 min). However, at 6 months follow-up, the 27 gauge group had significantly improved Best Corrected Visual Acuity (0.39± 0.13 logMAR) compared to the 23 gauge group (0.76± 0.37 logMAR), (p < 0.01). The 23 gauge group had the highest mean time of exit (9.5 ± 1.3 min.). Conclusion: When comparing the varied incision sizes associated with the 25-G and 23-G vitrectomy systems, the 27-G system yielded comparable results when done on a variety of conditions. Smaller-gauge vitrectomy systems have several advantages, but they also have some drawbacks, including as weaker instruments and a less effective treatment.