Objective To explore and analyze the efficacy of different doses of intravenous immunoglobulin （IVIG） combined with aspirin in the treatment of children with Kawasaki disease （KD）， along with its impact on lipid metabolism parameters， DeRitis ratio ［aspartate aminotransferase （AST）/alanine aminotransferase （ALT）］， and platelet parameters. Methods A retrospective analysis was carried out to gather the clinical data of KD children admitted to the pediatrics department of the hospital from January 2021 to January 2025. All the acquired data were sourced from the hospital's electronic medical record database and follow-up database. The children were grouped based on the dosage of IVIG. Specifically， children with KD treated with high-dose IVIG （3 g/kg） in combination with aspirin were assigned to the high-dose group， those treated with conventional-dose IVIG （2 g/kg） in combination with aspirin were assigned to the conventional-dose group， and those treated with low-dose IVIG （1 g/kg） in combination with aspirin were assigned to the low-dose group. To minimize the interference of baseline conditions， the propensity score matching method was employed to balance the baseline data of the three groups. Using the 1∶1∶1 nearest-neighbor matching method with a clamp value set at 0.03， 39 cases of data were ultimately obtained for each group. The therapeutic effects， lipid metabolism ［total cholesterol （TC）， high-density lipoprotein cholesterol （HDL-C）， triglycerides （TG）， low-density lipoprotein cholesterol （LDL-C）， apolipoprotein A1 （ApoA1）， very-low-density lipoprotein cholesterol （vLDL-C）］， platelet parameters ［platelet distribution width （PDW）， platelet count （PLT）， plateletcrit （PCT）， mean platelet volume （MPV）， large platelet ratio （P-LCR）］， coronary Z-score value， and safety of the three groups were compared. Results The high-dose group exhibited a higher total effective rate compared to the low-dose group （P < 0.05）. After one week of treatment， the levels of HDL-C in both the high-dose group and the conventional-dose group increased when compared to those before treatment （P < 0.05）. In all three groups， the levels of TG decreased （P < 0.05）， and the levels of ApoA1 increased （P < 0.05）. After one week of treatment， the levels of HDL-C and ApoA1 in the high-dose group were higher than those in the other two groups， whereas the ratios of TG and DeRitis were lower （P < 0.05）. After one week of treatment， the values of PDW， PLT， MPV， and P-LCR in all three groups decreased （P < 0.05）. The high-dose group had lower values of PDW， PLT， and P-LCR than the other two groups， and a lower value of MPV than the low-dose group （P < 0.05）. During the 12-week follow-up， the Z-score values of the right coronary artery， left coronary artery， and left anterior descending branch in each group were all lower than those before treatment （P < 0.05）， and the values in the high-dose group were lower than those in the other two groups （P < 0.05）， with no statistically significant difference between the other two groups （P > 0.05）. There was no statistically significant difference in the incidence of adverse reactions and cardiovascular-related complications （P > 0.05）. Conclusions High-dose IVIG combined with aspirin demonstrates a superior therapeutic effect on KD. It offers more advantages in short-term lipid regulation and platelet function regulation. Moreover， it can mitigate liver damage， reduce the DeRitis ratio， and diminish the risk of coronary artery injury.