Multigrid method is a well-known solver for linear boundary value problems. In this paper, we expand our interest into a nonlinear problem which has just one nonlinear term added to linear elliptic equation. We study two treatments, FAS and the Newton-multigrid method. Numerical values obtained by those two methods show similar efficiency. We annex the computational result of nonoverlapping DDM to the same nonlinear equation as further studies.