The invention discloses a method for improving the stability of beet root red. Aiming at the problems that chemical properties of beet root red in an aqueous solution are unstable and beet root red iseasily discolored by the effects of heat, pH, light and other environmental factors, the method adopts soybean protein fibers as a protection agent to improve the stability of the beet root red. After protection treatment, the thermal degradation rate of the beet root red at the temperature of 90 DEG C can be reduced to 24.1%. The method for improving the stability of the beet root red is simpleto operate, low in cost, and good in inhibition effect on the beet root red degradation caused by heat, and has a good application prospect in food industry and related fields.