<b>The Production of Instant Powder Fermented Soy Food Supplement Enriched with Rice Bran</b> Fermented soy bean or tempe has been documented as source of vegetable protein and consumed mainly by most Indonesian people living in Java Island. However due to having short storage life and also lack of vitamin and mineral become the main hindrance to develop the utilization of this product. The processing of fermented soy bean into probiotic powder supplement enriched with rice bran has been searched. Three stages of experiments were carried out. The first stage was to find out the effect of fermentation time on the characteristic and total microbial load of fermented soy bean. A single factor with six levels 4, 6, 8, 10, 12 and 14 hours with four replications were used to carry out this study. The second stage of experiment was to find out the effect of temperature and emulsifier concentration on the characteristic and storage life of the fermented powder food supplement. A randomize block design was used to carried out this study. The temperature at three levels 50, 55 and 60ÂșC as the first factor and emulsifier tween 80 concentration at two levels 0.3 and 0.4 w w as the second factor, all the treatments were repeated three times. Result from the first stage shown that the fermentation time of 12 hours has the highest total microbial load of 0.8x108 cells ml while the protein content was 2.894 w w, fat content 1.2209 w w, pH 3.6 and the ash content of 0.57 w w. Result from the second stage shown that the temperature of 500C and tween 80 at a concentration level of 0.3 w w, has total microbe of 0.24x108 cells ml and 282.67 mg 100 g isoflavone. The powder enriched with rice bran has a significant role to increase the body weight of rats. After 15 days of feeding the rats body weight increased about 30 w w. Fermentation, Foam mat drying, Instant Powder, Rice Bran, Soy Bean 1166-1171 Issue-6 Volume-2 Sri Kumalaningsih