Objective To analyze the effect of modified tension-reducing cosmetic suture combined with postoperative wound tension reduction and ion beam therapy on wound healing and scar repair in patients with facial trauma scars. Methods A total of 100 patients with facial trauma scars admitted to our hospital from February 2024 to February 2026 were selected as the research subjects. According to the random number table method, they were divided into the control group and the study group, with 50 patients in each group. The control group received modiffed tension-reducing cosmetic suture combined with postoperative wound tension reduction treatment, and the study group received ion beam therapy on the basis of the control group. The wound healing indicators, scar repair (VSS score) and skin barrier function were compared between the two groups. Results After treatment, the epithelialization time, complete healing time and wound edema duration in the study group were shorter than those in the control group, the VSS score was lower than that in the control group, the transcutaneous water loss was lower than that in the control group, and the stratum corneum hydration was higher than that in the control group (P<0.05). Conclusion Modiffed tension-reducing cosmetic suture combined with postoperative wound tension reduction and ion beam therapy can effectively accelerate wound healing in patients with facial trauma, improve scar appearance and enhance skin barrier function.