Abstract: This paper presents a transmission matrix method to calculate reflection of fields of multiplies carbon fiber sheet. By formulating the fields on two sides of the interface between adjacent plies with a clear matrix form and connecting the corresponding matrixes in cascade, the reflection of arbitrary number and arbitrary orientation of plies can be treated easily. The numerical results show that the reflectance varies rather slowly with the input electric field polarization and illustrates that the various plies compensate the anisotropic nature of each others when they are assembled. The method shows the possibility of simplifying the field computation problems relevant with carbon fiber parts.