Objective To observe the blood lipid levels in children with first-onset type 1 diabetes mellitus (T1DM), and to analyze its correlation with the level of glycosylated hemoglobin (HbA1c) in children. Methods Clinical data of 168 children with T1DM admitted to Baoding Children's Hospital from January 2018 to June 2019 were retrospectively analyzed, and 100 healthy children in the same period were selected as control group.Differences on blood lipids such as total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) were compared between the two groups.Pearson analysis and multiple linear regression method were used to analyze the correlation between serum lipid level and HbA1c level in children with T1DM. Results The levels of TC, TG and LDL-C in T1DM group were significantly higher than those in control group (t=4.691, 7.705, 4.119, P＜0.001), while HDL-C level in T1DM group was significantly lower(t=3.845, P＜0.05).The level of HbA1c in dyslipidemia group was significantly higher than that in normal blood lipid group[(13.09±2.71)% mmol/L vs.(11.78±2.56)% mmol/L, t=3.209, P<0.05].Pearson correlation analysis showed that HbA1c level was positively related to TC, TG and LDL-C levels(r=0.547, 0.514, 0.438, P＜0.05), while significant correlation between HDL-C and HbA1c level was not found (r=0.109, P>0.05).Multiple linear regression analysis showed that TC and TG levels were closely related to HbA1c level (β=0.008, 0.045, P<0.05). Conclusion The proportion of dyslipidemia is higher in children with T1DM.Higher level of HbA1c indicates higher risk for dyslipidemia, which should be given more consideration in clinic practice.