Peaches are easily perishable fruit, and their quality is quickly lost after harvest. In this study, “Hujingmilu” peach ( Prunus persica L.) fruit was treated with citric acid (CA) and stored at 20°C for 15 days. Fruit decay and quality were evaluated during the storage period. Compared with the control, CA treatment did not inhibit climacteric ethylene release, but CA was significantly effective at maintaining firmness, inhibiting decay, and preventing a decrease in titration acid (TA). CA treatment inhibited the increase in total soluble solids (TSS), sucrose, and fructose in the first week after fruit harvest, but then their content was significantly higher in CA‐treated fruits than that in the control group. The decrease in malic acid and citric acid was significantly prevented by CA treatment. During storage, the concentrations of C6 volatile compounds decreased rapidly whereas lactones sharply increased, and the concentrations of δ‐decalactone, γ‐decalactone, and γ‐dodecalactone were found to be significantly high in CA fruits compared with the control after the eighth day of storage ( p < .05). Similarly, higher contents of chlorogenic acid, neochlorogenic acid, catechin, and L‐epicatechin were maintained in fruits treated with CA during the same storage period ( p < .05). Our findings suggest that treatment with 10 g/L citric acid can reduce postharvest decay and effectively maintain the texture, flavor, and nutrition quality of peach fruit.