Objective To explore the efficacy and safety of CO2 fractional laser combined with derma roller in the treatment of patients with facial depressed scar. Methods A total of 40 patients with facial depressed scar admitted to the Department of Plastic and Cosmetic Surgery, Suzhou 100 Hospital from May 2022 to March 2024 were selected and divided into the control group and the experimental group by the random number table method, with 20 patients in each group. The control group was treated with CO2 laser, and the experimental group was treated with CO2 fractional laser combined with derma roller. The clinical efficacy, scar recovery and adverse reactions were compared between the two groups. Results The total effective rate of treatment in the experimental group was 80.00%, which was higher than 50.00% in the control group (P <0.05). After treatment, the diameter and depth of the depressed scar in the experimental group were lower than those in the control group (P <0.05). There was no significant difference in the incidence of adverse reactions between the two groups (P >0.05). Conclusion The application of CO2 fractional laser combined with derma roller in the treatment of patients with facial depressed scar can effectively promote scar recovery. The treatment effect is good, without increasing the incidence of adverse reactions, offering higher efficacy and safety.