Objective To study the dynamic changes of the activities of superoxide dismutase (SOD), amylase (AM) and alkaline phosphatase (ALP) and of the contents of epithelium growth factors (EGF) and insulin growth factors (IGF-1) in human colostrum (lactation 1-7 days postpartum). Methods A total of 118 samples of human colostrum were taken from 20 healthy women postpartum. The activities of SOD, AM and ALP in human colostrum were determined by methods of pyrogallol autoxidation, colorimetry of iodine-starch and pyrocatechol phosphate respectively. EGF and IGF-1 contents in human colostrum were measured by radioimmunoassay. Results The SOD activity of human colostrum increased slightly during lactation 1-4 days postpartum, from (18.7?2.2) kU/L to (22.5?2.9) kU/L, then it tended to decrease, being (11.2?2.1) kU/L on the 7th day. The SOD activities in lactation 1-5 days postpartum were significantly higher than that on day 7 ( P