Abstract: A new modified engineering wake model,Park-Gauss model,is proposed under the assumption of wake region’s linear expansion and Gaussian distribution of radial wind velocity in Park model. This new model adopts niche genetic algorithm and takes the effects of atmospheric stability on wind farm layout optimization into consideration. The optimization result of the micro location layout of a wind farm with constant wind speed and single wind direction is to arrange the wind turbine in the first and the last row of the vertical wind direction. The result also shows that the atmospheric boundary layer’s stability has a significant influence on the optimization of wind farm’s micro-sitting layout. Under the condition of unstable atmospheric boundary layer,wind farm can install the largest number of wind turbines and has the highest power generation capacity and utilization efficiency,followed by the neutral state and the stable state.