Abstract: By the relativity experiment of some physiological indexes and heat-resistance in varieties of daylily, some physiological indexes that would be considered as the system of heat-resistance for the daylily were selected. The experiment on the change trend of the physiological indexes in 6 varieties’ leaf of daylily from field experiment with different heat-resistance under the normal and high temperature condition indicated the water content change and the rate of free water and tied water of leaf increased more evidently under high temperature when they have lower heat-resistance, but the content of soluble proteins and the activities of SOD, POD and CAT increased more evidently under the same higher temperature in the varieties with higher heat-resistance. All of those physiological indexes would be considered as the system of heat-resistance select for the daylily.