At present, the scour problem of foundation for offshore wind turbine is difficult to be solved effectively. It is necessary to develop an economic and effective scour prevention measure. Physical model tests are carried out for the scour prevention measures based on bionic grass, and the influence of bionic grass size and arrangement form on the scour prevention effect of monopile foundation for offshore wind turbine is discussed. The results show that there is an optimal value for the height and arrangement radius of bionic grass considering the scour prevention effect and cost. When the height of bionic grass is 1.5m and the arrangement radius of bionic grass is 1.7 times the pile diameter, the scour prevention effect of bionic grass is better and more economical.