Abstract: In order to provide reference for engineering application of the woven composite, a new unit cell division method and a mechanical model were put forward to predict the engineering elastic constants. The model adopted raceway shape as the cross-section of yarns, and prediction methods of volume fractions and elastic modulus were established based on the micro structure and geometric parameters of it. Then the finite element method was used to analysis the mechanical behavior under the circumstances of axial-tensile load, and the stress state was revealed. The results shows that the predicted values using finite element method agree well with the theoretical calculation values, thus the model and analysis method of elastic constants is verified.