Objective To analyze the effect of pulsed dye laser combined with fractional erbium laser on scar improvement and quality of life in patients with post-acne hypertrophic scar. Methods A total of 60 patients with post-acne hypertrophic scar admitted to the Department of Aesthetic Dermatology, Yangzhou Guangling iFace Medical Beauty Clinic from April 2023 to April 2024 were selected as the research subjects, and they were divided into the control group and the observation group by the envelope method, with 30 patients in each group. The control group was treated with fractional erbium laser, and the observation group was treated with pulsed dye laser combined with fractional erbium laser. The scar improvement, skin barrier function and quality of life were compared between the two groups. Results After treatment, the scores of color, thickness, softness and vascular distribution in the observation group were lower than those in the control group (P<0.05). After treatment, the TEWL of the observation group was lower than that of the control group, while the stratum corneum water content was higher than that of the control group (P<0.05). After treatment, the score of Acne-QoL in the observation group was higher than that in the control group (P<0.05). Conclusion For post-acne hypertrophic scar, the combined application of pulsed dye laser and fractional erbium laser can not only repair the scar appearance and skin function from the surface to the inside, but also fundamentally improve the patients' subjective quality of life and self-confidence, achieving a good therapeutic effect of simultaneous physical and mental improvement.