Objective To observe the therapeutic effect and safety of CO2 lattice laser combined with botulinum toxin A injection technology in the treatment of surgical suture scar after facial trauma. Methods From July 2019 to January 2021, 60 patients with surgical suture scar after facial trauma in the Department of Medical Aesthetics of North Jiangsu People' s Hospital were randomly divided into experimental group and control group, with 30 cases in each group. The control group was treated with CO2 lattice laser, and the experimental group was treated with local injection of botulinum toxin type A after CO2 lattice laser treatment. The Vancouver scar scale (VSS) score, clinical efficacy, adverse reactions and patient satisfaction were compared between the two groups. Results The VSS weight scores of the two groups at 1 and 6 months after treatment were lower than those before treatment, and those in the experimental group was lower than those in the control group, the difference was statistically significant (P<0.05). The total effective rate of the experimental group was higher than that of the control group 1 month after treatment, and the difference was statistically significant (P<0.05); there was no significant difference in the total effective rate between the two groups 6 months after treatment (P>0.05). The satisfaction of the experimental group was higher than that of the control group, and the difference was statistically significant (P<0.05). There was no significant difference in the incidence of pigmentation between the two groups (P>0.05). Conclusion CO2 lattice laser combined with botulinum toxin type A injection technique is effective in the treatment of surgical suture scar after facial trauma, which can improve the appearance of scar without increasing the probability of adverse reactions and has high application safety.