Intraocular lens (IOL) implantation is required after vitrectomy combined with cataract surgery in diabetic retinopathy patients. However, the question of whether an IOL should be implanted in stage I after vitrectomy or stage II during silicone oil filling has been controversial, and there has been no systematic review of this clinical issue.WanFang, SinoMed CNKI, VIP, PubMed, Embase, and Cochrane Library databases were systematically searched for relevant studies. The deadline was May 8, 2021. All studies of stage I or II IOL implantation in patients with diabetes who underwent vitrectomy were included. Revman 5.3 software was used for the meta-analysis.Four studies, involving 253 eyes, were included. This study analyzed the literature with a common outcome index by meta-analysis and systematically evaluated the literature without a common outcome index. Four studies compared the efficacy and safety of the 2 sequential surgical methods in patients with diabetic retinopathy. The results of the meta-analysis showed that there was no significant difference in the efficacy and safety of stage II IOL implantation when compared with stage I IOL implantation (P > .05). One study showed that stage II cataract surgery with oil extraction resulted in better postoperative visual acuity and fewer complications than stage I cataract surgery with vitrectomy. One study showed that stage II IOL implantation during oil extraction had better postoperative visual acuity than stage I IOL implantation during vitrectomy without increasing surgical complications.Vitrectomy combined with stage II IOL implantation is safer and more effective than stage I in patients with diabetic retinopathy; however, more clinical studies are needed to verify this.Copyright © 2022 the Author(s). Published by Wolters Kluwer Health, Inc.