Abstract: A total of 8 Mongolian sheep （n=4） and Neimonggol cashmere goat （n=4） with perpetual rumen fistula were chosen to investigate the differences of their calcium,phosphorus and nitrogen metabolism in different diets by 2x2 factorial experimental design. The results showed that the metabolic rate of calcium, phosphorus and nitrogen were higher when the Mongolian sheep and Neimonggol cashmere goat were fed with hey than those when they were fed with corn straw pellet. The metabolic rate of calcium, phosphorus and nitrogen of Mongolian sheep were higher than those of Neimonggol cashmere goat under high level diet nutrition. While the metabolic rate of calcium and nitrogen of Mongolian sheep were lower than those of Neimonggol cashmere goat under low level diet nutrition, the metabolic rate of phosphorus was higer.