The purpose of this study was to determine the extraction of hydrolysate protein from waste materials (rice grain and rice beverages) in order to increase the value of domestic raw materials. The goal was to create protein beverage products containing rice protein hydrolysates that are customized to the needs of athletes for post-workout muscle restoration. Carbohydrates were extracted from rice paste using an amylase enzyme, followed by protein extraction using the Protease G6 enzyme. The E/S SL ratio, temperature, and time were investigated, with the extraction taking place at a pH of 7.0. The Central Composite Design approach was used in the experimental design to change the extraction conditions. The protein concentration and the concentration levels were determined. The concentration data were then submitted to 95 percent confidence level Analysis of Variance (ANOVA) to find significant differences. To visualize the relationship between protein concentration and the interaction between the E/S SL ratio, temperature, and extraction duration, a contour plot was generated. The results showed that increasing enzyme proportions and temperatures between 50 and 60 degrees Celsius boosted protein concentration. Lower E/S SL ratios and longer extraction times enhanced protein concentration. An E/S, SL ratio of 5%, a temperature of 52 degrees Celsius, and an extraction time of 180 minutes were shown to be ideal conditions for extracting protein from rice grains utilizing Protease G6 enzyme. The final protein content was 3.14 g/100 ml. These findings suggested that Protease G6 can be a viable alternative for developing rice protein beverages for athletes and health-conscious individuals.