To determine Pb level in blood, we usually .used to pull out about 5ml blood from venous vessel and this sample was digested with acids to decompose organic matter and then determined the Pb contents by Atomic Absorption Spectrophotometer with flame. But recent trend in quan titating Pb in small amount of sample is very much recommended in clinical chemistry specially pediatrics, and industrial hygiene and occupational health area. Authors tried to determine Pb contents in small amount blood of $25{mu}l$ by using capillary tube method and got the possibility of determination of ng amount of Pb in $25{mu}l$ whole blood sample without any pretreatment of sample.