Researchers optimized the extraction of flavonoids from pigeon pea leaves using cellulase. They varied enzyme amount, temperature, time, and pH to maximize flavonoid yield. The best conditions were found to be 8.65 mg of enzyme, 33.88℃ temperature, 2.02 hours of extraction time, and pH 5.02. The predicted and experimental flavonoid yields were very close, showing the reliability of the optimized extraction process. These findings will help in future research on utilizing pigeon pea leaves for flavonoid extraction.