Icing of plane will jeopardize it fight. The flow and droplet-impingement property of a three-dimensional model of DLR plane is analyzed thought Fensap.CFD method and Spalart–Allmaras turbulence model were used .Certain the influence of different environment parameter to droplet-impingement property by altering specified parameter and we can finally know the influence of environment to plane icing. The result indicate that：Higher velocity results in smaller water efficiency and smaller water diameter also results in smaller water efficiency.