Abstract: To accurately predict the macroscopic elastic properties of 3D angle-interlock woven composites, interior and surface unit-cells mesoscopic solid models were established for numerical analysis based on the geometric parameters measured in CT images, and surface unit-cells were modeled in the form of integrated surface unit-cells. Then a tensile test in warp direction was conducted for 3D angle-interlock woven ultra-high molecular weight polyethylene (UHMWPE) fiber/polyurethane composites. The results show that the predicted macroscopic elastic modulus values of the composites based on two unit-cells models are in good agreement with the experimental values. The tensile modulus in the warp direction of the integrated surface unit-cells is smaller than that of the interior unit-cells. During the tensile test in the warp direction, stress concentration tends to occur at the interface among warp yarns, the end of weft yarns along the width and the interface between warp yarns and matrix. When the number of weft layers is less than 30, the effect of surface region on the overall mechanical properties of the composites should be considered.