Abstract: In this paper, the effects of cooking time on cell structure, free-starch content, physicochemical properties and digestive characteristics of the whole potato powder were studied. The result showed that: With the extension of cooking time, the conductivity of potato cooking suspension increased from 24 μm/cm to 1285 μm/cm, and the iodine blue value (BVI) increased from 8.31 to 19.00, which indicated that after cooking pretreatment, the cell breakage rate and damage degree of whole potato meal increased, and the release amount of intracellular substances and the content of free-starch increased. The colors of whole potato flour was light yellow without browning and blackening. The heat damage of starch particles increased, the viscosity of whole starch increased. The whole potato powder was more easier to gelatinize, and its digestibility increased. The content of fast digestible starch(RDS) increased from 46.39% to 70.74%, and the content of resistant starch(RS) decreased from 29.08% to 11.60%. In summary, the results showed that the functional characteristics of potato powder were closely related to its cooking time, which would provide theoretical reference for the preparation of potato powder and the development of subsequent products.