Abstract: A method for conducting structural fatigue life testing of a bearing, in which a cam embedded in the bearing under test generates a rotational dynamic radial expansion and transmits the expansion through the bearing to a load collar compactly mounted on the periphery of the bearing, forcing the load collar to deform synchronously with the expansion, thereby applying, together with the cam, a rotational dynamic strain pressure load, mainly in the radial direction in both inward and outward directions, to the bearing, based on the elasticity of the load collar itself, as a test load for the structural fatigue life testing of the bearing. Based on the above method, the present invention also provides a holding mechanism that provides a rotation-resistant support for the load collar and a bearing rotation test rig capable of assembling the holding mechanism.