The work aims to carry out the study on potato sterilization based on plasma water treatment, in order to solve the problem of easy infection of microorganisms in potatoes. With potatoes as the raw material, and the total number of colonies on the potato surface as the index, the bactericidal effect of plasma water prepared by different currents, water volume, preparation time and potato treatment time at 25 ℃ was studied. The results showed that, under the following conditions, i.e. 15 L water volume, 1 h plasma water preparation time, 10 min potato cleaning time and 6A current, the plasma water prepared had the best bactericidal effect, the total number of colonies (2.15 lg CFU/g) on the potato surface was significantly less than that of the control group (5.24 lg CFU/g) and water treatment group (4.22 lg CFU/g), and the plasma water treatment would not change the color or hardness of the potato. The results of SEM showed that, the plasma water could break the microbial cells on the surface of potato and inactivate them, but had no effect on the epidermal structure of potato. This study shows that, the plasma water treatment can effectively reduce the microbial content of potato surface, provides a new physical green sterilization way for potato preservation and has certain reference and guidance for industrial applications.