"Cam" rice bran was considered a waste product from rice, which is rich in natural compounds and protein owing to its outstanding nutritional value. This study aimed to establish an optimization model for extracting protein from rice bran, with two responses: extraction yield (%) and protein content (%). The variable parameters included were pH (8.5-9.5), stirring time (3.5-4.5 h), and enzyme incubation temperature (85-95°C). The coefficient of determination for both models were above 0.95, indicating a high correlation between the actual and estimated values. The maximum extraction yield and protein content were achieved when the conditions were set at pH of 9.02, stirring time of 4.02 h, and extraction temperature of 90.6°C. Under these optimum conditions, the predicted protein extracted from rice bran was 43.03% (moisture

KEYWORDS: rice bran, protein content, optimization, nutritional value