Abstract: The paper aims to quantitatively discuss the effect of meteorological conditions on rice paniclestem. Based on the physiological characteristics and growth rules of rice, the authors built a model of rice growth according to the vegetative growth period and reproductive growth period by the method of dynamics. On this basis, the authors studied the effect of three comprehensive factors (including temperature, precipitation, sunshine) on rice panicle-stem with Forcal and Matlab. The results showed that: (1) the energy advantage brought by vegetative growth could not be completely transformed into the storage advantage of rice panicles, while the environmental condition of reproductive growth period was more critical to rice yield; (2) both poor nutrition and over luxuriant growth brought about negative effect on the accumulation of rice panicle; (3) the model could quantitatively simulate the growth of rice from the perspective of energy, and could well reflect the influence of meteorological condition on rice growth.