Abstract: High temperature stress can cause great losses to rice production, but the research about its damage mechanism is still at the primary stage. We studied the changes of main physiological indexes of different heat resistant rice varieties under high temperature stress, in order to analyze the relationship between the physiological indexes and rice heat resistance. The results showed that there were differences of heat resistance among different rice varieties, and different heat resistant rice varieties could be screened by heat resistance coefficient. High temperature stress could have a great influence on physiological indexes of different heat resistant rice varieties, as the prolonging of treatment time, there was a peak of most physiological indicators. The peak of physiological indexes of strong heat resistant varieties appeared later than those of heat sensitive varieties. Correlation analysis on heat resistance coefficient and physiological indexes showed that there were a negative correlation between heat resistance coefficient and physiological indexes (POD, CAT, SOD and Pro), positive correlation between heat resistance coefficient and MDA. Further, the correlation coefficient between the heat resistance and CAT activity reached -0.75222^**. Under high temperature stress, rice physiological indexes would change a lot. Each physiological index had a peak, showing that high temperature heat harm was the feedback mechanism of regulation of stress materials. There was certain correlation between change of physiological indexes and heat resistance under high temperature stress.