Ozone treatment can effectively delay the decay of many fruit during postharvest storage. However, little is known about the ozone-induced metabolites. In this study, Satsuma mandarin fruit were treated with 2 μg L −1 ozone gas for 5 h. Results showed that ozone treatment not only effectively delayed the fruit decay, but also significantly reduced fruit respiratory intensity, delayed fruit degreening and prolonged shelf-life of Satsuma mandarin fruit during postharvest storage. After gas chromatography coupled to mass spectrometry (GC–MS) analysis, a total of 96 metabolites were detected in Satsuma mandarin peel (albedo + flavedo), including 55 primary metabolites and 41 volatile compounds. After ozone treatment, the contents of many metabolites increased significantly at 1 d, mainly including soluble sugars and organic acids, which might play a regulatory role in ozone-induced fruit resistance. Moreover, a great number of metabolites related to antioxidant and antibacterial activity were also induced at 4 d by ozone treatment, which might effectively improve the disease resistance, delay the decay, and prolong the shelf life of Satsuma mandarin fruit.