Objective To investigate the relationship between serum glucagon-like peptide-1(GLP-1),monocyte chemoattractant protein-1(MCP-1),insulin-like growth factor binding protein-3(IGFBP-3)and glycolipid metabolism,bone metabolism and microvascular complications(MC)in children with type 1 diabe-tes mellitus(T1DM).Methods A total of 211 children with T1DM(T1DM group)admitted to Handan Cen-tral Hospital,Xingtai Traditional Chinese Medicine Hospital,Baoding First Central Hospital and Handan Ma-ternal and Child Health Hospital from January 2021 to February 2023 were selected,patients were divided into MC group(63 cases)and non-MC group(148 cases)according to whether MC was complicated within 1 year,and 108 healthy children who underwent physical examination during the same period were selected as control group.The levels of serum GLP-1,MCP-1,IGFBP-3 and glucose and lipid metabolism indexes[fasting plasma glucose(FPG),fasting insulin(FINS),glycosylated hemoglobin(HbA1c),homeostasis model assessment of insulin resistance(HOMA-IR),total cholesterol(TC),triglyceride(TG),high density lipoprotein cholesterol(HDL-C),low density lipoprotein cholesterol(LDL-C)]and bone metabolism indexes[bone specific alkaline phosphatase(BALP),osteocalcin(OST),type I collagen cross-linked C-terminal peptide(CTX)]were detec-ted.The correlation between serum GLP-1,MCP-1,IGFBP-3 and glucose and lipid metabolism,bone metabo-lism in children with T1DM were analyzed by Pearson and Spearman correlation coefficient.Taking MC in children with T1DM as the dependent variable,the influencing factors were determined by multivariate uncon-ditional Logistic regression model,and the predictive value of serum GLP-1,MCP-1 and IGFBP-3 for MC were analyzed by receiver operating characteristic curve.Results The levels of serum GLP-1,FINS,HDL-C,BALP,OST and CTX in the T1DM group were lower than those in the control group,while the levels of MCP-1,IGFBP-3,FPG,HbA1c,HOMA-IR,TG and LDL-C in the T1DM group were higher than those in the control group,the differences were statistically significant(P<0.05).Serum GLP-1 in children with T1DM was negatively correlated with FPG,HbA1c,HOMA-IR,TG and LDL-C,and positively correlated with FINS,HDL-C,BALP,OST and CTX(P<0.05).MCP-1 and IGFBP-3 were positively correlated with FPG,HbA1c,HOMA-IR,TG and LDL-C,and negatively correlated with FINS,HDL-C,BALP,OST and CTX(P<0.05).Follow-up for 1 year,the incidence of MC in 211 children with T1DM was 29.86%(63/211).Elevated HbA1c,HOMA-IR,LDL-C,MCP-1 and IGFBP-3 were independent risk factors for MC in children with T1DM,and elevated GLP-1 was an independent protective factor(P<0.05).The area under the curve of ser-um GLP-1,MCP-1 and IGFBP-3 combined to predict MC in children with T1DM was 0.919,which was grea-ter than 0.781,0.788 and 0.794 predicted by serum GLP-1,MCP-1 and IGFBP-3 alone(P<0.05).Conclu-sion The decrease of serum GLP-1 level and the increase of MCP-1 and IGFBP-3 levels are related to glyco-lipid metabolism,bone metabolism disorder and MC in children with T1DM,the combined application of ser-um GLP-1,MCP-1 and IGFBP-3 has a good predictive value for MC in children with T1DM.