The invention discloses a comprehensive utilization method for potato residues, potato juice and modified starch based on juicing of potatoes. The method comprises the following steps: with cleaned, sorted and sieved potatoes as a raw material, carrying out juicing on the potatoes in the process of extraction of starch from the potatoes; separating starch so as to obtain potato residues and potato juice; and separately conveying the potato residues and the potato juice to respective treating zones for treatment via pipelines or conveyer belts. According to the invention, juicing is carried out on the basis of extraction of starch from the potatoes and then comprehensive treatment is carried out on the products, i.e., the potato residues, the potato juice and the starch, so the industrialization level of the potato industry is improved and application of potatoes as staple food grain is promoted. In the process of processing, flour and potato modified starch adsorb and bond with water molecules, and cross-linking and coagulation occur, so a novel crystal structure is formed; the novel crystal structure is low in solubility in water, enzymatic hydrolysis is reduced, and digestion and absorption are slowed down; and thus, the composition of starch in wheaten food can be changed, and rise in blood sugar and the reaction of plasma insulin after meal are delayed.