Objective To explore the effect of carbon dioxide fractional laser on wound healing time and pain degree in the treatment of pigmented nevus. Methods A total of 100 patients with pigmented nevus who were treated in Yidu People's Hospital from January 2023 to May 2025 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 electroion laser, and the observation group was treated with carbon dioxide fractional laser. The wound healing time, pain degree, clinical efficacy, adverse reaction rate, satisfaction and quality of life were compared between the two groups. Results The wound healing time of the observation group was shorter than that of the control group, and the VAS score was lower than that of the control group (P <0.05). The total effective rate of the observation group (96.00%) was higher than that of the control group (76.00%) (P <0.05). The incidence of adverse reactions in the observation group (2.00%) was lower than that in the control group (14.00%) (P <0.05). The satisfaction of the observation group (98.00%) was higher than that of the control group (80.00%) (P <0.05). After treatment, the scores of quality of life in the observation group were higher than those in the control group (P <0.05). Conclusion The application of carbon dioxide fractional laser in the treatment of pigmented nevus can effectively shorten wound healing time, reduce pain degree, improve treatment effect, improve the quality of life of patients, and the incidence of adverse reactions after treatment is low, and the patient satisfaction is high.