Based on water absorption and bean paste rate (dry matter), the soaking and cooking process of red adzuki bean were optimized. Then, the dynamic changes of main nutritional and functional components during the process were tracked. The results showed that the water absorption of red adzuki bean was the highest (94.67±1.29)% under the soaking temperature of 45 ℃ and soaking time of 12 h. The bean paste rate was the highest (65.69±0.68)% to be cooked at 110 ℃ for 40 min with a solid-to-solvent ratio (soaked red adzuki bean:water) of 12 (g/mL). The nutritional and functional components of red adzuki bean decreased significantly during the process of sand making (P<0.05). The loss rates of main functional components such as flavonoids, polyphenols and tannin were significantly higher than protein, fat and ash (P<0.05). In particular, the loss rate of flavonoids in soaking, cooking and sand washing process was relatively high (39.62%, 48.42%, 13.08%). The content of protein in the finished red adzuki bean paste was 21.48% (dry matter), while the polyphenol and tannin were enriched in the bean dregs with the contents (dry matter) of 162.30 mg/100 g and 14.26 mg/100 g respectively, which is poten-tial for value-added utilization.