Trace elements play an extremely important role in the human body, and their deficiency or excess is closely related to human health. Trace elements have a special affinity with hair, and the accumulation of trace elements in the body in the hair, and their high or low levels indicate the risk of certain diseases. Trace element examination means checking the amount of trace elements by means of instruments. At present, health care units at all levels in China, especially maternal and child health care units, children’s hospitals, general hospitals, etc., have made testing of human elements (lead, zinc, copper, calcium, magnesium, iron, etc.) a routine item. Methods to check the trace elements of babies: 1. Collect blood samples, take venous blood or peripheral blood, and test the trace elements in blood. 2. Collect human hair and test the trace elements in hair, this method is the most widely used. The content of trace elements in baby hair is higher than in other parts such as blood, saliva and urine, and it is more stable and easier to analyze. However, when taking hair, it will be affected by the cleanliness of the hair itself and the part where it is taken, and there will be a big difference, so it can only be used as a reference. Trace element test program: test the content of zinc, calcium, magnesium, iron, copper and lead 6 elements. The results of the trace element test should pay attention to whether the elements are abnormal due to other diseases or the trace element deficiency due to malnutrition, if it is caused by diseases, it needs to be treated according to the diseases; if it is caused by malnutrition, it needs to supplement the deficient trace elements and use the medicine reasonably according to the doctor’s guidance.