This experiment is carried out to study effect of choline-deficient diet on serum and liver lipid contents of male rats. The experimental animals use 36 male Sprague-Dawley rats weighing about $100{pm}3g$. They are classified into 7 groups and fed to experimental diets which are composed of 0.8% choline-supplement of deficient diets in addition to 14% corn oil, 14% corn margarine and 14% lipids mixed with 4% corn oil and 10% corn margarine, respectively. After feeding for 4 weeks, I measure lipid concentration of serum and liver, and the result are as follows. 1. The choline-deficient diet group decreases slightly the rates of weight gain and feed efficiency as compared with those of the choline-supplement diet group, but increases liver weight. 2. The choline-dificient diet group decreases the serum concentrations of total cholesterol (TC), free cholesterol, HDL-choelsterol, VLDL, LDL-cholesterol and phospholipid (PL), but increases the contents of triglyceride and the ratios of cholesterol/HDL-cholesterol and triglyceride/PL, and indicates no remarkable-difference in the ratio of TC/PL. 3. As compared with the choline-supplement diet group, the choline-deficient diet group contains the higher liver contents of total lipids, free cholesterol and triglyceride, and gives little difference in the liver contents of total cholesterol and phospholipid(PL), and presents the higher ratios of VLDL, LDL-cholesterol/HDL-cholesterol and TG/PL in the liver.4. In the choline-deficient diet group, the coutents of serum and liver lipid is not influenced by the kind of dietary fat. On the other hand, the choline-supplemented diet group indicates a significantly lower content of phospholipid in the corn margarine-added diet group than in the corn oil-added diet group. As aforementioned results, I think that the choline-deficient diet induces fatty liver in male rats without relation to kind of fatty acid, and cholines-upplement diet with saturated fatty acid makes the more decrease of liver phospholipid than that with polyunsaturated fatty acid.