The bond characteristics and failure mechanisms of externally bonded reinforcement (EBR) fiber-reinforced polymer (FRP) composites on concrete under fatigue loading are not as well understood as their behavior under static loading. Most existing studies on carbon FRP (CFRP) strengthened reinforced concrete (RC) structures under fatigue cyclic loading primarily focus on demonstrating the effectiveness of CFRP in enhancing fatigue life. However, the bond behavior and the growth rate of fatigue damage zones, which are crucial for the performance of RC structures strengthened with externally bonded CFRP, remain largely unexplored. This paper presents an experimental study that investigates the behavior of EBR CFRP-to-concrete bonded joints under fatigue cyclic loading. Specifically, it examines the growth rate of fatigue damage zones of these bonded joints subjected to direct pull-out fatigue loading, with a focus on CFRP laminates under varying maximum cyclic loads relative to the static critical load, while maintaining a constant load ratio of R = 0.1. The study observed interfacial debonding between the CFRP and adhesive during fatigue cycles, while concrete cohesive failure occurred under static loading. Additionally, it was found that higher maximum cyclic loads significantly accelerated local bond propagation.