Abstract: In this paper, the half-reaction time of the reaction between hydrazine and its derivatives with nitrous acid is measured using spectrophotometry and stopped-flow injection device. Using Gaussian09 and HyperChem, hydrazine and its derivatives have been structurally optimized and some quantization parameters are calculated. Combining the half-reaction time and the quantization parameters, and using statistical regression analysis, QSAR model of the reaction between hydrazine and its derivatives with nitrous acid is established. The results show that total energy of molecules is the most important influencing factor in the reaction, and the half-reaction time increases with total energy of the molecule except for allyl hydrazine, the reaction rate decreases with the increase of total energy of the molecule.