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Extrusion is a method that has been widely used to modify the functional properties of food ingredients. The objective of this study was to investigate the impacts of extrusion with gum arabic and xanthan gum on the physical properties and starch digestibility of bean powders of two varieties: Merlot Small Red and Fuji Otebo. The beans were ground to pass through a screen with an opening of 0.5 mm and properly blended with 1%, 3%, or 5% (db) gum arabic or xanthan gum. The bean powders and the blends were extruded (APV Baker MP 19T-25 twin-screw extruder) under the same conditions. The obtained extrudates were dried at 50°C overnight and then ground to pass through the same screen. The addition of the food gums increased the die pressure and specific mechanical energy during extrusion, and the increasing effect, dependent upon the gum concentration, was more obvious with xanthan gum. The extrusion, with and without the food gums, caused complete starch gelatinization and protein denaturation of the bean powders. Compared with the respective control bean powders before and after the extrusion, the presence of gum arabic decreased the viscosities of the bean powders, whereas xanthan gum increased the viscosities. The different effects could be attributed to the substantially higher viscosity of xanthan gum than gum arabic. The addition of food gums enhanced the water-holding capacity of the extruded bean powders of both varieties, and the increasing effect was slightly greater with xanthan gum at the same level of addition. The addition of gum arabic and xanthan gum did not show a remarkable effect on the starch digestibility of the bean powders before and after the extrusion. Extrusion with food gums can effectively alter different functional properties of bean powders but not their starch digestibility.