AbstractCracks in structures often grow due to local multiaxial loading situation. Saving structure’s reliability requires fracture mechanical criteria, which were validated by experimental investigations. This article presents 3D-mixed-mode criteria for cyclic loadings, which will be compared with experimental determined threshold values under 3D-mixed-mode-loadings for different materials as well as crack kinking and twisting angles. Using specially developed specimens and loading devices the experiments are performed for pure mode I-loading, pure mode II-loading, pure mode III-loading and 2D- as well as 3D-mixed-mode-loading combinations. The comparison of mixed-mode threshold values, resulting from fatigue experiments, with 3D-criterion by Richard reveals a widely validity and a generally conservative behaviour of the criterion by Richard.