Abstract: The actual operating conditions of wind turbines are complex, which leads to strong unsteady characteristics between wind turbines in the wind farm, and causes unsteady aerodynamic load of the upstream and downstream wind turbines due to the unsteady wake effect. In this study, the unsteady characteristics for the wake effect of multiple wind turbines are investigated under the gust wind condition. Firstly, an unsteady wake simulation method is established by coupling the LES (large eddge simulation) and the actuator line model, and the feasibility and accuracy are verified using the Nibe wind turbine. Meanwhile, the development characteristics of a single wind turbine wake is unveiled. Then, taking the NREL 5 MW wind turbine as an example, numerical simulations are performed for multiple wind turbines under the gust wind condition. The characteristics of unsteady wake effects and the development mechanism of the wake vortex structures under the gust wind condition are discovered. Finally, aerodynamic load characteristics of the upstream and downstream wind turbines are analyzed and summarized under the gust wind condition. The present analyses and results are significant in guiding the wind farm layout and wind turbine design.