Objective To investigate the efficacy and safety of cross-finger digital artery island flap repair in the treatment of skin defects following finger replantation. Methods A total of 80 patients with skin defects after finger replantation admitted to our hospital from May 2022 to June 2025 were enrolled and randomly divided into two groups using a random number table, with 40 cases in each group. The control group underwent conventional free full-thickness skin graft repair, while the study group received cross-finger digital artery island flap repair. Surgical recovery indicators and graft survival rate were compared between the two groups. The Patient and Observer Scar Assessment Scale (POSAS) and the Vancouver Scar Scale (VSS) were applied to evaluate the quality of scar appearance at 3 and 6 months postoperatively. Postoperative complications in both groups were recorded. Results The wound healing time and length of hospital stay in the study group were significantly shorter than those in the control group, and the graft survival rate was higher (P<0.05). At 3 and 6 months after surgery, the POSAS subscale scores and VSS scores in both groups decreased over time, and the scores in the study group were significantly lower than those in the control group at the same time points (P<0.05). The total incidence of postoperative complications in the study group was significantly lower than that in the control group (P<0.05). Conclusion Cross-finger digital artery island flap repair can markedly enhance the success rate of skin defect reconstruction in finger replantation, shorten the postoperative recovery period, deliver favorable cosmetic outcomes, and result in fewer complications, thus warranting clinical promotion and application.