<p>Six fatigue tests were conducted to investigate the fatigue behaviour of CFRP-repaired compact- tension specimens (CT specimens), considering the effects of CFRP material type, patch configuration and patch layer numbers. Beach marking technique and digital image correlation (DIC) technology were employed to depict the crack propagation and the strain distribution on the specimens. The differences in fatigue life and fatigue crack growth rates (FCGR) results reveal that CFRP patches can prolong the fatigue life, even tripling the cycle number in a test. There is a salient advantage in double-side repairing compared to its one-side counterpart. However, the CFRP sheet layer number doesn’t guarantee the strengthening efficacy. The specimen repaired by CFRP plate had a mixed failure mode of adhesive layer failure and CFRP debonding. The failure mode of CFRP- sheet repaired specimens was a mix of CFRP debonding, delamination and adhesive layer failure.</p>