Certain miscellaneous beans have a low glycemic index (GI) and may reduce the risk of chronic metabolic disorders, including type 2 diabetes and obesity, by modulating postprandial glucose homeostasis and blood lipid levels. In this study, red kidney bean flour and wheat gluten were used as raw materials, and long-chain inulin phosphate monoester (PFXL) was added to improve the quality of red kidney bean dough, prepare high-quality steamed bread, and explore its health effect on type 2 diabetes. The results showed that the addition of PFXL improved the water distribution and rheological properties of coarse grain dough and enriched the flavor of coarse grain steamed bread. In addition, the optimized steamed bread exhibited a low glycemic index (eGI = 51.76), which could reduce fasting blood glucose and glycated serum protein by 21.55 % and 26.11 %, respectively, and could significantly improve oral glucose tolerance and blood lipid levels in diabetic mice and had a certain protective effect on liver injury. Overall, these findings provide a scientific basis for the development of functional foods.