The effect of diets(high fat, high fat high energy, pectin, cellulose) on adipocyte of epididymal fat pads were investigated in 70 male rats for 8 weeks. The rats were assigned to a control(C), high fat(HF) and high fat high energy(HFHE) group for 4 wks. During the next 4 wks, reassigned to one of three treatments (high fat, pectin supplemented, cellulose supplemented) in the HF group and one of three treatment (high fat high energy, pectin, cellulose) in the HFHE group. Therefore, the total experimental groups were 7 (C, HF, HF-P, HF-C, HFHE, HFHE-P, HFHE-C). Parameters evaluated and compared for each diet were body weight, total energy intake, feed efficiency ratio and weight changes in epididymal fat pads. The results are summarized as follows ; 1) There was no significant difference in body weight gain among the groups. 2) Total energy intake was higher in the C group than other groups. 3) Feed efficiency ratio (F.E.R) of the HF and HFHE groups were greater than C group(2, 4 weeks). However, there were no significant differences between the HF and HFHE groups. 4) Epididymal fat pads(EFP 100g/B.W) of the FH and HFHE groups were higher than C group (2, 4 weeks). However, there were no significant differences between the HF and HFHE groups. There was no significant difference in weight gain of epididymal fat pads among the groups(8 weeks). 5) Cell number and cell size of epididymal fat pads of the HF and HFHE groups were higher than the C group. The pectin and the cellulose supplementation groups decreased cell number and cell size of epididymal fat pads. Especially, the pectin supplementation group decreased than the cellulose supplementation in HFHE group. Therefore, we can concluded that the HF and the HFHE diet has no effect on the epididymal fat pads.