Abstract: Wrinkle defect is one of the common defects in manufacturing process of composite structures. It is valuable to study the impact of wrinkle defects and their grinding treatment on failure behavior, which lies basement for the assessment of manufacturing defects. In this paper, both experimental and numerical analysis methods were used to study the influence of out-of-plane wrinkle defect and its grinding treatment on the bending failure behavior of laminates. In terms of experiment, nine groups of samples were prepared with artificial wrinkle defects by the ‘transverse strip method’. Four-point bending test were carried out to evaluate the bending failure process. In numerical analysis, a high fidelity 3D finite element model of wrinkled laminates were developed to analysis its progressive failure process. The test results show that the bending bearing capacity of laminates can be slightly reduced by out-of-plane wrinkle defects with a decrease within 5%. The grinding treatment would significantly further reduce the capability. The influence degree of grinding is positively related to the size of wrinkles. The influence of grinding wrinkles located on the compressive side is more significant than that on the tensile side. The ultimate strength of SSW-U/L decreased by 15.91% and 11.54%, and that of SLW-U/L decreased by 29.78% and 21.57%. Numerical results reveals that, for the case of wrinkles located at the compressive side, the fiber compression failure firstly occurs at the edge of the wrinkled layer. For the grinded laminates, when the wrinkles are located on the compression side, the layer delaminated at the grinded end firstly, and subsequently the fiber compressive failure occurs in the compressive layers. When the wrinkles are located on the tensile side, the delamination is derived by matrix tensile failure in the grinded layer, and is induced, and then fiber compression failure occurs in the compressive layers.