Objective To explore the effects of whole quinoa flour addition on the quality and in vitro digestion characteristics of biscuits.Methods Whole quinoa flour, at varying proportions (0%, 10%, 20%, 30%, 40%, and 50%), is added to wheat flour to investigate the effects of whole quinoa flour addition on the quality and in vitro digestion characteristics of biscuits.Results Compared with the control group without whole quinoa flour, the groups with whole quinoa flour addition show gradually increased moisture content of quinoa biscuits as well as their hardness gradually decreasing and toughness first increasing and then decreasing as the addition of whole quinoa flour increases. When the addition of whole quinoa flour is 30%, the toughness of the biscuits reaches its maximum. As the addition of whole quinoa flour gradually increases, the flavor of the biscuits changes significantly (P<0.05), and the sensory score and total starch hydrolysis rate gradually decrease. When the addition of whole quinoa flour exceeds 20%, the glycemic index (GI) value of the biscuits is below 55, which indicates they are low GI foods.Conclusion Adding whole quinoa flour can reduce the in vitro digestibility and GI of biscuits.