Abstract: To investigate the effects of whole black bean powder and black bean extracts on the estimated glycemic index (eGI) in an in vitro simulation, and to optimize the extraction process of anthocyanins from black bean peel by single-factor experiments combined with response surface methodology.First, black bean extracts were prepared by enzymatic extraction and ultrasound-assisted enzymatic extraction. Using starch hydrolysis rate and eGI as evaluation indicators, the effects of anthocyanins and other components on the in vitro starch digestion were analyzed. Single-factor experiments were further conducted to systematically investigate the effects of extraction temperature, extraction time, solid-liquid ratio and enzyme ratio on the extraction yield of anthocyanins from black bean hulls, and response surface methodology was adopted to optimize the extraction conditions. The results showed that among whole black bean powder and black bean extracts, anthocyanins from black bean hulls exhibited the strongest inhibitory effect on starch hydrolysis and the best in vitro hypoglycemic activity. The optimal extraction conditions obtained by response surface optimization were extraction temperature of 63 ℃, extraction time of 43 min, solid-liquid ratio of 27：1mL/g, with an extraction yield of 5.26 mg/g. This study demonstrates that black bean anthocyanins possess favorable in vitro hypoglycemic potential. They can be used as natural active factors for the development of functional glycemic-control foods, providing theoretical and technical support for the research and development of such functional foods.