The invention provides a modeling method and a simulation method for a kinetic model of a wind turbine gearbox. The modeling method comprises the following steps: establishing a physical model of the wind turbine gearbox, importing the physical model into kinetic analysis software, and setting physical properties of parts of the wind turbine gearbox; according to a topological structure of the wind turbine gearbox, setting a connection relationship among the parts in the model of the wind turbine gearbox, so that a rigid body model of the wind turbine gearbox is obtained; carrying out finite element analysis on parts of a shaft system of the wind turbine gearbox, so that a flexible body model of the shaft system of the wind turbine gearbox is obtained; and importing the flexible body model of the shaft system of the wind turbine gearbox into the rigid body model of the wind turbine gearbox, and replacing the corresponding parts of the shaft system, so that a flexible body model of the wind turbine gearbox is obtained. The modeling method adopting the technical scheme has the advantages that the rigid body model of the wind turbine gearbox requires fewer system resources during computing, so that the model can be rapidly examined, the modeling time can be reduced, and the modeling efficiency can be improved.