The research aimed to study the fresh-cut carrots. Fresh-cut carrots were treated with NO donor sodium nitroprusside (SNP) and soaked with 0.1mmol/L by 2h. The changes of sensory qualit and physiological and biochemical indexes of 15d at 4℃ were determined. The effect of NO treatment on fresh-keeping of fresh-cut carrots were analyzed. The results showed that NO effectively reduced the occurrence rate of fresh- cut carrots.NO treatment could improve the antioxidant-related enzyme activity, such as ascorbate peroxidase (Ascorbate peroxidase, APX), catalase （Catalase, CAT). NO treatment could reduce the electrical conductivity of fresh-cut carrots’ tissue, inhibited the activity of ipoxygenase (Lipoxygenase, LOX), reduced the accumulation of malondialdehyde(Malondialdehyde, MDA), delayed the occurrence of membrane lipid peroxidation, reduced the degree damage of fresh-cut carrots’ cell membrane. NO treatment also inhibits enzymatic activities associated with phenylpropane metabolism, such as polyphenol oxidase (Polyphenol oxidase, PPO), peroxidase (Peroxidase, POD), phenylalanine ammonia lyase（Phenylalanine ammonia lyase, PAL), and the accumulation of secondary metabolites such as total phenols and flavonoids, and thus delay the process of fresh-cut carrots’ whitening.NO improves the antioxidant capacity of fresh-cut carrots and reduces the enzyme activity associated with the phenylpropane metabolic pathway to improve the sensory quality of the product and prolong the shelf life.