The technology of vacuum pre-cooling was applied to the broccoli's keeping fresh at 5℃, whose effect on the physiological activities of broccoli was studied. The results showed that the respiration rate and ethylene production florets were inhibited, and sensory quality was improved. Weight loss was decreased by 2.18% at the end of storage. At the same time, the degradations of chlorophyll and vitamin C were delayed by vacuum pre-cooling followed. Chlorophyll content fall by about 50% of the original in a vacuum pre-cooling group had been postponed for 12 days. Vacuum pre-cooling also delayed senescence of broccoli by regulating the activity of antioxidant enzymes.