Objective To explore the relationship between serum iron(SI)metabolism and glucose and lipid metabolism in patients with type 2 diabetes mellitus(T2DM).Methods A total of 170 T2DM patients hospitalized in the Department of Endocrinology,Lanzhou University First Hospital from 2019 to 2021 were included.During the same period,30 healthy individuals from physical examination center were selected as the normal control(NC)group.Based on HbA1c control,T2DM patients were divided into subgroups with good blood glucose control(H1,HbA1c＜7%,n=39),poor glucose control(H2,7%＜HbA1c＜9%,n=63)and very poor glucose control(H3,HbA1c＞9%,n=68).According to the level of blood lipids,T2DM patients were divided into subgroups with normal blood lipids(L1,n=36)and high blood lipids(L2,n=134).Results Compared with NC group,age,SBP,DBP,BMI,serum ferritin(SF),FPG,FIns,HOMA-IR,TyG,TG,LDL-C and SUA increased inT2DM group(P＜0.05),while SI,TF,total iron binding capacity(TIBC),DI,HDL-C and eGFR decreased(P＜0.05).The levels of TF and TIBC in H3 subgroup were lower than those in H1 subgroup(P＜0.05).LDL-C of L2 subgroup was higher than that of L1 subgroup(P＜0.05),while HDL-C was lower than that of L1 subgroup(P＜0.05).Pearson correlation analysis showed that SF was positively correlated with HbA1c,TyG,TG and SUA(P＜0.05),and negatively correlated with HDL-C and eGFR(P＜0.05).TF was positively correlated with HDL-C and eGFR(P＜0.05),but negatively correlated with age,SBP,DBP,TyG and SUA(P＜0.05).Multiple linear regression analysis showed that SF and FPG were influencing factors for HbA1c in T2DM patients.Conclusion SI metabolism is closely related to glucose and lipid metabolism in T2DM patients.