Determination of the lipolytic activity in various organs of rats were done by means of organ homogenate in vitro, the significance of the lipolytic activity was more characterized by the inhibition study of the Lipoprotein Lipase (LPL). The activity of the lung tissue was high followed by the cardiac muscle or adipose tissue. After force feeding fat meal or after heparin administration in vitro, the significant elevation was observed. And also after carbon tetrachloride poisoning or aseptic pneumonia induced by silver nitrate solution injection, the lipolytic activity in the lung increased with the endogeneous lipid transportation from the depot fat to the liver tissue. The histological character of the lung tissue is rich in arterioles and capillaries and also rich in mast cells and the lung has a anatomical speciality ; the first organ to be approached by exogeneous lipid. These findings suggest that the lung is one of the organs which produce LPL and may display some role in the exogeneous and endogeneous lipid transportation