With the increase in the unit capacity of wind turbine, the structure size and flexibility of parts also increase significantly, which make dynamic load of the machine set during operation become more and more complicated. In order to guarantee stability of the unit operation, it is a research hot spot problem that through control strategy to reduce dynamic load of unit. The linear model of wind turbine was researched. Five quantity state space control simulation model of 1.5 MW wind turbine was established to reduce dynamic load in the operation process through controlling the blade pitch angle and generator torque. The superiority of the modern control algorithm is shown in reducing the load comparing with the load calculation result of traditional PI control method.