This balance study was performed to investigate nutritional effects of guar gum and calcium supplement for 8 weeks. 36 male rate of Sprague-Dawley strain weighing 50g were blocked into six groups : 5CN, 5GN, 5CS, 5GS, FFN, 10GN. Food intake, body weight gains, FER, PER, bioavailabity of energy, protein, fat, Ca and P, and Ca & P content of femur and kidney was measured. The results obtained in this study were summarized as follows: (1) Feed intake, weight gains, FER, PER and bioavailabilities of protein and P and the contents of Ca & P in femur of 5GB were significantly higher than 5CN and 5CS (p<0.05) but was not significant different with those 5GN. Fat bioavailabilities of 5GS was significantly lower than 5CN and 5GN (p<0.05) but was not significant different with those of 5CS. Ca contents of kidney of 5GS was significantly higher than 5CN and 5GN(p<0.05) but was not significant different with those of 5SC. (2) According to guar gum levels feed intake. FER and PER were not sifgnificantly different among groups but body weight gains, bioavailabilities of energy, protein, fat and Ca, Ca & P content of femur was significantly decreased (p<0.05). Bioavailabilities of P was significantly increased according to the guar gum levels (p<0.05). Ca contents in Kidney of 10GN was significantly higher those of 5GN(p<0.05) but P contents in kidney was not significant difference by guar gum levels. Therefore 5% supplemental guar gum in diet of obese man and diebetics could be recommended. But it should be careful in using 10% guar gum in diet.