Objective To establish reference intervals of serum iron,magnesium,zinc and copper in healthy infants aged 0 to 12 months in Changchun,in order to provide reference for clinical diagnosis and treatment. Methods According to industry standards of health WS/T 402-2012 and after screening by clinical and laboratory standards,8 905 infants aged 0 to 12 months who took physical examination in the First Hospital of Jilin University were enrolled from January 2014 to December 2017.Serum iron,magnesium,zinc and copper were tested by Hitachi 7600-210 automatic biochemical analyzer and were classified according to age and gender.Data were analyzed by SPSS 21.0 and then the reference intervals for age and gender were obtained. Results Serum iron levels gradually decreased with months and serum magnesium concentration gradually increased with months.After gradually increasing with months,serum zinc level in boys and girls trended to peak at 7 to 8 months old and 5 to 6 months old,respectively,and then gradually declined.Serum copper level increased with months,peaking at 11 to 12 months old.There were age differences on the reference intervals of the four trace elements,and serum copper began to show gender differences from 4 to 12 months old. Conclusion It is of great significance to establish age-and sex-related reference intervals for serum trace elements in infants for the correct assessment of infant development.