Objective To evaluate the clinical effect of CO2 fractional laser in the treatment of traumatic scar. Methods From January 2022 to June 2023, 60 patients with post-traumatic scar who were treated in the Laser Cosmetic Center of the Department of Dermatology, the First Affiliated Hospital of Anhui Medical University were selected as the research objects. According to the type of scar, they were divided into the depressed scar group and the hypertrophic scar group, with 30 patients in each group. Both groups were treated with CO2 fractional laser. The scar status, clinical efficacy, doctor's visual score (IVA) and adverse reactions were compared between the two groups. Results The VSS score of the two groups after 2 and 4 times of treatment was lower than that before treatment, and the VSS score of the depressed scar group was lower than that of the hypertrophic scar group (P <0.05). The total effective rate of treatment in the depressed scar group was 83.33%, which was higher than 40.00% in the hypertrophic scar group (P <0.05). The IVA score of the depressed scar group was higher than that of the hypertrophic scar group after 2 and 4 times of treatment (P <0.05). The incidence of adverse reactions in the depressed scar group was 13.33%, which was lower than 36.67% in the hypertrophic scar group (P <0.05). Conclusion CO2 fractional laser is effective in the treatment of traumatic scar, and is more effective in the treatment of depressed scar than hypertrophic scar, the symptoms are improved more clearly and the safety is higher.