In this study， three strains(R.oligosporus FW-1， G.candidum FW-2， R.azygosporys FW-3) preserved in the laboratory were used as starters to study their fermentation and transformation ability on soybean dregs. Taking the unfermented soybean dregs before inoculation as a control， sampling was performed at 48， 72 h and 96 h， respectively， and the metabolic changes of protein， fat and isoflavones in the soybean dregs were systematically analyzed. The results showed that the protein and fat in soybean dregs showed an overall downward trend during the fermentation process， and amino acids and fatty acids showed an overall upward trend. In terms of the degradation ability of soybean dregs protein and the increase of essential amino acids， R.oligosporus FW-1 showed a relatively outstanding advantages， the degradation rate of protein and peptide was 12.2% and 25.2%， and the increase rate of essential amino acids was 12.3%. In terms of the degradability of soybean dregs fat， the increase of unsaturated fatty acids and the modification of isoflavones， R.azygosporum FW-3 showed outstanding advantages. Its degradation rate of soybean dregs fat was as high as 78.0%， and fatty acids were increased by 2.3 times， among which the content of unsaturated fatty acids was increased by 2.5 times. The conversion of isoflavones from glycoside type to aglycon type increased by 10.2 times. The two strains (R.oligosporus FW-1， R.azygosporys FW-3) showed a strong ability to degrade the nutrients of bean dregs， and a strong ability to transform their functional components， but also showed that the individual differences. This study provides a theoretical basis for the development of targeted high value-added soybean dregs.