A N\|S method for solving the flow around a wing with deflection of flap is presented. Using the combination of patched grid and domain decomposition techniques, the complex flow around this kind of configuration is effectively solved. An internal coupling condition satisfied the conservation of flux is used in the domain decomposition method. The spatial flux terms are discretized by using central difference scheme and the time integration is performed by using explicit scheme in the flow solver. Numerical results show that the present method is effective one for solving the flow around wing with flap deflection.