In order to study the dynamic characteristics of the maximum power point tracking (MPPT) of the doubly fed induction generator (DFIG), the MPPT control model of the power signal feedback algorithm is established on the Matlab/Simulink simulation platform. Taking the rectangular wind speed as an example, the transition time of MPPT static operating points and output energy of wind turbine are deduced by theory. The influence of different inertia of turbine on the dynamic power, speed tip speed ratio and wind energy efficiency of wind turbine is analyzed by simulation and theory. The dynamic power characteristic of MPPT of doubly fed wind turbine is described with the kinetic energy of rotor. It indicates that the greater inertia time constant, the lower the wind energy utilization factor. Finally, the dynamic characteristics of MPPT under different wind speeds are compared. Rotating speed tracking ability under random wind is worst, rotating speed tracking ability under gust and progressive wind is better.