Abstract: Apple fruit (Fuji)fruit was used as materials to study the effects of postharvest 2 mmol·L^-1 of ASA treatment on lesion development inoculated with T. roseum and reactive oxygen metabolism. The results indicated that 2 mmol·L^-1 of ASA effectively inhibited lesion diameter and natural incidence development of apple fruit tissue inoculated with T. roseum increased during storage at room temperature (p<0.05). The results also showed that ASA treatment promoted the hydrogen peroxide (H₂O₂)content and O₂^-·production rate and enhanced the activities of NADPH oxidase (NOX), superoxide dismutase (SOD), peroxidase (POD)while inhibited the catalase (CAT)activity of apple (Fuji)fruit during late storage stage (p<0.05), and improved the antioxidant system activity, then increased disease resistance and could maintain storage quality.