Okara, also named soy pulp is the by-product of the soy milk and tofu production process. Because the production of soy-texturized proteins from pilot plant will generate a lot of wastes, an attempt to make the value added from okara should be considered. However, the wastes contain high amount of proteins that can be useful for further food product development. Since the Lactobacilli (lactic acid bacteria) possess the ability to digest large protein molecules into small peptide chains and the bacteria are generally used in the food processing products. It would be thus interesting to investigate the digestibility of the Lactobacilli to okara. In this study, three species of the lactic acid bacteria (L. brevis, L. fermentum, and L. rhamnosus) were selected. Each of the Lactobacilli was cultured in the yeast-extract depleting MRS media and okara was used as nitrogen source instead. All cultures were performed at 37 °C for six different fermentation times (0, 3, 6, 9, 12 and 24 hours). No inoculation set was used as a control. The amount of proteins was extracted from the supernatants, and quantitatively measured the Quant-iT Protein Assay Kit. The results showed that the fermentation with L. brevis for 9 hours gives the highest amount of total proteins (5.12 mg/g of dried okara) when compared to those from the other two. On the other hand, after processing through the 3 kDa-MW cut-off ultrafiltration, the fermentation with L. fermentum for 12 hours gives the best yield of the low molecular weight peptide (2.26 mg/g of dried okara). The supernatant containing small peptide chains from the fermented okara by L. fermentum were subsequently analyzed by the HPLC/MS to estimate their mass. This optimization process will be applied for the semi-pilot scale in development of food processing products containing okara derived small peptides.