Abstract: 80 mesh red bean powder, corn flour, glutinous rice flour as the main raw material, oatmeal, adlay powder, buckwheat powder as auxiliary materials. Defining the Water absorption index (WAI) as the vital quality parameter and basing on the optimum recipe obtained from the red bean solid beverage, the relationship between main operation parameters of twin-screw extruder and WAI was studied through single-factor and response surface experiments. Two regression equations on WAI and four varietals factor was established. Results indicated that:under the condition that moisture content of 15.89%, screw speed 160r/min, barrel temperature 180℃, feed rate 18Hz (1Hz=1.7r/min) , WAI=5.05±0.03. Rheological properties research showed that:The mass fraction 15% puffed powder form stable suspension liquid, on condition of constant shear rate at 256s-1, its viscosity decreased rapidly on 0¹00s and viscosity decreased relatively flat on 100¹000s.