Zinc and copper levels were determined by atomic absorption spectrophotometry, in the hair and plasma of 81 Chilean infants of both sexes, comprised within an age range of two to 36 months, after routine clinical examination at a Peripheral Health Service. The children were eutrophic, free from chronic pathologies, and their birth weights were over 2,500 grams. The infants were distributed within seven age groups and the mineral levels found were correlated mainly with age and sex.