Abstract: Objective To explore the effect of combined application of pulsed dye laser (PDL) and ultra-pulsed fractional carbon dioxide laser (UFCL) in the treatment of pediatric large burn scars at early stage. Methods One hundred and twenty pediatric patients with large burn scars at early stage conforming to the study criteria were admitted to the People′s Hospital of Hunan Province from January 2016 to December 2019. Their data were retrospectively analyzed by the method of single case-control study. There were 78 males and 42 females with age of (4.2±0.8) years and scar area of (100.3±0.7) cm². PDL combined with UFCL was used for the first time. The treatment interval of PDL was a month and the treatment interval of UFCL was 3 months. The total treatment cycle was 6 months, with 2 PDL treatments alone and two combined treatments. Before the first combined treatment and 6 months after two combined treatments, the curative effect was assessed using Patient and Observer Scar Assessment Scale (POSAS) by doctors and family members of pediatric patients. Satisfaction degrees of the family members of pediatric patients were recorded, and the overall satisfaction rate was calculated 6 months after two combined treatments. The adverse effects during the whole treatment course were recorded. Data were statistically analyzed with paired t test. Results (1) Six months after two combined treatments, the scores of pediatric patients′ scar vascularity, pigment, thickness, relief, pliability, surface area, and overall valuation in POSAS by doctors and the scores of pain, itch, color, stiffness, thickness, irregularity, and overall valuation in POSAS by family members of pediatric patients were all significantly lower than those before the first combined treatment (t=16.6, 16.0, 16.9, 14.9, 20.8, 29.3, 30.7, 20.4, 29.3, 18.1, 27.9, 25.8, 20.8, 45.3, P<0.01). The overall evaluation scores by doctors were (8.1±0.8) and (2.7±0.6) points, and the overall evaluation scores by family members of pediatric patients were (8.2±0.8) and (2.4±0.5) points respectively before the first combined treatment and six months after two combined treatments. (2) Six months after two combined treatments, 110 (92%) family members of pediatric patients were very satisfied with the curative effect, 6 (5%) family members of pediatric patients were satisfied, and 4 (3%) family members of pediatric patients were relatively satisfied with no unsatisfied reported. The overall satisfaction rate was 97% (116/120). (3) During the treatment, pruritus and rash appeared in 5 pediatric patients 3 to 4 days after the first treatment; pigmentation appeared in 3 pediatric patients 3 weeks after the first treatment; pruritus and vesicle appeared in 1 patient 1 week after the third treatment. No adverse effects such as aggravated scar or infection were observed on the wounds. Conclusions In treating pediatric large burn scars at early stage, PDL combined with UFCL has demonstrated significant effect with short treatment cycle, few adverse effects. The combined treatment can alleviate symptoms and improve the quality of pediatric patients′ life, and is worthy to be popularized and applied in clinic.