The work aims to study the characteristics change of fresh-cut lotus roots after plasma-activated water (PAW) treatment during cold storage and the effect on the preservation effect of fresh-cut lotus roots so as to extend the shelf-life of fresh-cut lotus roots. PAW was generated by a cold plasma device. The bactericidal performance of PAW at different plasma treatment time was measured. Fresh-cut lotus roots were treated with PAW and stored in a cold storage environment. A variety of performance indexes such as weight loss, hardness, browning, malondialdehyde content, ascorbic acid content and polyphenol oxidase activity were measured every 2 d. The results showed that after treatment with PAW-9 (generated through 9 min of plasma treatment), the total bacterial count was significantly lower (2.35 lg(CFU/g)) than that of deionized water treatment (3.46 lg(CFU/g)). Compared with the control group, which showed browning and softening on the 4th day, the PAW-treated group maintained better quality during the 8 d of storage. Specifically, the PAW-treated group exhibited superior weight loss, hardness, and browning compared with the control group. Furthermore, PAW treatment effectively inhibited the activity of polyphenol oxidase, preserved ascorbic acid content, and suppressed the increase of malondialdehyde. Among the PAW, PAW-9 generated through 9 min of plasma treatment demonstrated the best preservation effect. PAW treatment can maintain the quality of fresh-cut lotus roots, inhibit browning, and prolong the freshness period effectively, which has a good application prospect.