A cohesive zone model to deal with high-cycle fatigue of composite bonded joints under mixed-mode I+II loading is developed. The model assumes a linear traction-relative displacements softening and uses a single parameter to simulate the cumulative damage resulting from static and fatigue loading. Finite element analyses considering the Single-Leg Bending test were conducted to verify the performance of the proposed method under different modified Paris laws and load ratios. It was verified that the model is able to capture all those effects with accuracy which proves the adequacy of the whole procedure concerning mixed-mode I+II fatigue/fracture characterization of composite bonded joints.