The effect of the cellulose content of diet on the metabolizability of starch and tallow was determined. The metabolizable energy values for starch and tallow were calculated from the difference in the metabolizable energy content of the reference diet which was substituted a proportional content of cellulose for test material and diet containing starch or tallow. The hatched White Leghorn male chicken were fed a commercial diet for the first week and experimental diets for the next three weeks during the four weeks of the experiment. Body weight gain, feed conversion, and retention of nitrogen did not show significant difference among the chicken fed diets containing various levels of cellulose contents during the experimental period. When the proportion of cellulose in the diet was increased, the metabolizable energy of the diets showed a stepwise reduction. When the cellulose content of the diets was higher, the starch of 99.1% was metabolized, and the metabolizable energy value amounted to 4142 ㎈ per gram. and the tallow of 82.3% was metabolized and the metabolizable energy value reached to 7764 ㎈ per gram. But, when the cellulose content of diets was lower. the metabolizability of starch was significantly lower value, being 65%, than that of higher cellulose content of diet. The metabolizability of the tallow was 62% which was also lower value than that of higher cellulose content.