In this paper, a new multiscale homogenization method is introduced to calculate the field and current distribution inside carbon fiber reinforced polymer composites submitted to an external electromagnetic field. In the microscopic scale, the real structure of the material is taken into account and electromagnetic and electrical equivalent properties are calculated using finite-element method (FEM). In the macroscopic scale, these properties are introduced in an impedance network or in an anisotropic-finite elements method according to the working frequency. The simulating results are in accordance with experimental ones and will allow a better modeling of composites.