Abstract: Appropriate calcium treatment could obviously slow down the physiological activities of post-harvest loquat fruit. The results of the experiment indicated that spraying with calcium chloride, Ca2+ content of loquat fruit rose, the breath peak was postponed and the peak was lowered. The cell membrane Permeability, the content of the MDA showed an upward trend and the rate declined, which was lower than the control, with the increase of concentration of calcium. Calmodulin increased first and then decreased, and the peak increased with the increase of calcium concentration while the control was declining. The activities of SOD and CAT increased gradually and then declined with the prolong of the storage. The higher the calcium concentration, the smaller the rate. POD, PAL and other activities had an upward trend. But the effect of activity of PAL became obvious with the increase of calcium concentration. The activity of POD increased and its rate became smaller and lower than the control with the increase of calcium concentration. And it was discovered then that calcium concentration was too high which caused the slightly physiological diseases of the fruit. This explained that by using 1.5 percent calcium chloride spraying on the leaves and fruit at the same time can effectively slow down post-harvest physiology of loquat fruit and will not lead to physiological diseases.