Objective To explore the effect of local flap repair combined with fine tension-reduction cosmetic suture on scar formation in patients with facial trauma. Methods A total of 100 patients with facial trauma admitted to the Second People's Hospital of Jiulongpo District from January 2023 to January 2024 were selected, and they were divided into the control group and the observation group by the random number table method, with 50 patients in each group. The control group was treated with debridement and suture, and the observation group was treated with local flap repair combined with fine tension-reduction cosmetic suture. The treatment effect, scar formation, pain intensity and adverse event rate were compared between the two groups. Results The total effective rate of the observation group (96.00%) was higher than that of the control group (80.00%) (P <0.05). The scores of scar color, vascular distribution, softness and thickness in the observation group at 3 and 6 months after surgery were lower than those in the control group (P <0.05). The VAS scores in the observation group at 3, 5 and 7 days after surgery were lower than those in the control group (P <0.05). There was no significant difference in the incidence of adverse events between the two groups (P >0.05). Conclusion Local flap repair combined with fine tension-reduction cosmetic suture has a good effect in the treatment of patients with facial trauma. It can effectively reduce scar formation, help to relieve pain, reduce the incidence of adverse events, and has good application safety.