Numerical Homogenization gives numerical approximations of the effective properties of a composite material. In the case of periodic composite, multi-scale modeling allows to consider only a Representative Volume Element (RVE). In this paper, we propose an original finite element method based on fictitious domain principle, in which the RVE is represented by a structured mesh and the inclusions are represented by independent and non matching meshes. The integral computations on inclusions meshes are substituted into the structured mesh of the RVE, with the help of a connection matrix.