Abstract: The impact of typhoon on Liaoning has become much more serious in recent years. Rainstorm disasters induced by typhoon have a great influence on human activities, which have being the common and most serious one due to its heavy rain, long duration as well as broad influence. Therefore, it’s greatly significant to study the characteristics of typhoon rainstorm and its forecasting technique. The track variation of the typhoon ‘AMREY’ was explained by atmospheric circulation’s evolution and the double typhoon effect, and the causes of rainstorm induced by ‘DAMREY’ were also comprehensively analyzed based on routine weather map data as well as its physical quantities. Results showed that: there’s a strong dynamic condition in ‘DAMREY’ circulation itself. The inburst of weak cold advection strengthened the convergence of the perturbation in low layer and a strong vertical motion was aroused coupling with westerly jet due to the convergence in low layer and divergence in up layer. The join of cold and warm air provided a favorable condition for rainstorm. In addition, abundant water vapor was provided by southwest jet along with a wide and deep water vapor transfer belt. At last, the physical quantities of the initiation of typhoon rainstorm were summarized for typhoon rainstorm forecast in the future, which was more helpful to improve the forecast accuracy in this region.