This paper investigated the fresh-maintaining effects of Na5（NH4）16[Mo57Mn6（NO）6O174（OH）3（H2O）24]·44H2O （abbreviated Mo57Mn6） processing on fresh-cut apples， and continuously measured five indexes， including weight loss ratio， browning degree， malonaldehyde yield， peroxidase （POD） activity and polyphenol oxidase （PPO） activity. The results indicate the processing of Mo57Mn6 can hold water and keep color effectively， and can decrease the yield of malondialdehyde and inhibit the activity of polyphenol oxidase within a week. It also can activate the activity of peroxidase in the late storage. In conclusion， Mo57Mn6 can effectively extend the shelf life of apples. The research results can provide some experimental basis for the development of novel fresh-keeping agents of fruits and vegetables， and enlarge the application scope of polyoxometalates.