In attempts to determine the cause of hypertriglyceridemia, a model animal was established. This model is useful to analyze on the relationship between food ingestion and hypertriglyceridemia. When backcrossing of the Watanabe heritable hyperlipidemic rabbit and the Japanese white rabbit, individual rabbits with high triglyceride values were identified. A novel hereditary postprandial hypertriglyceridemic rabbit, characterized by normal serum triglyceride values under conditions of fasting and high levels of serum triglyceride value by ingestion of food was thus obtained.