Abstract: In order to investigate the effects of pre-harvest salicylic acid (SA) spraying on post-harvest quality and antioxidant metabolism of prunes (Prunus domestica L.), 'French' prune trees in Xinjiang were treated with SA solutions at concentrations of 1, 2, or 4 mmol/L. Applications were made during four key developmental stages: fruit set, expansion, color change, and maturity. A control group received water sprays. Following harvest, fruit were stored at 1.0±1.0 ℃ and 90%~95% relative humidity. Quality parameters and antioxidant metabolism indicators were assessed at 15 days intervals over the 90 days storage period. Results demonstrated that pre-harvest spraying of SA could significantly maintain the hardness, soluble solids content and titratable acid level of plum fruits during post-harvest storage, and inhibit the color blackening, respiration and weight loss rate of fruits. The 2 mmol/L SA treatment proved most effective. At the end of storage, the activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), ascorbate peroxidase (APX), and glutathione reductase (GR) in the 2 mmol/L SA-treated prunes were 1.17, 1.40, 1.54, 1.23, and 1.26 times higher than the control group, respectively (P<0.05). The contents of ascorbic acid (AsA) and glutathione (GSH) were 2.70 and 1.08 times higher than the control group, enhancing the antioxidant enzyme activities and effectively maintaining AsA and GSH levels. Additionally, the production rate of superoxide anion (O₂⁻·), hydrogen peroxide (H₂O₂), and malondialdehyde (MDA) accumulation, as well as cell membrane permeability, were suppressed. This indicateed that spraying SA before harvest could maintain the post-harvest quality of prunes by enhancing their antioxidant metabolism capacity.