Fatigue significantly impacts engineering structures, especially reinforced concrete, which endures millions of cyclic loads over its service life. Understanding the progressive degradation of concrete’s mechanical properties under fatigue is critical. This paper reviews existing degradation models, encompassing stiffness degradation, strength degradation, and strain development models. Then, these models are compared in terms of accuracy and applicability, and potential research directions for concrete damage modeling under fatigue are proposed. This work aims to serve as a valuable resource for future investigations and engineering applications.