The species of pathogen fungi of honey peaches("Hujinmilu" of Shanghai Nanhui District) as well as the effects of Thymol on the mycelial growth were investigated,and the effects of post-harvest treatment with modified atmosphere packaging and thymol on the physiology and fresh-keeping of honey peaches were studied under 3℃ storage.The results showed that the mainly pathogen fungi which caused the postharvest diseases of peaches were Alternaria,Monilinia fructicola,Cephalothecium,Rhizoctonia;and the thymol dramatically changed the physiological of the peach.It decreased the loss of fruit firmness and titrable acidity,increased membrane permeability.Thymol treatment significantly enhanced POD activity,and inhibited PPO activity.After 28 days,the good fruits rates was 79.1% by using 500 mg/L thymol.The results demonstrate that thymol treatment can increase the quality during storage.