The present paper deals with the problem of the micromechanics analysis of the elastic constants of one ply plain weave composite. In fact, we demonstrate the validity of this method proposed in the case of two-dimensional textile structural composite, which has orthotropic symmetry in the (x-y) plane by assuming undulation in two direction. We have used two techniques which are called stiffness averaging (S.Av.) and compliance averaging (C.Av.). The Mathematica symbolic manipulation is used and a Mathematica program is included.