The present study investigated the quasi-static tensile and fatigue properties of the center-cracked thin and thick aluminum plate single-side repaired with T300 carbon fiber reinforced epoxy composite patches. The repair efficiency of the damaged thin and thick aluminum plates was compared with the tensile and fatigue properties, and the effect of the initial crack length on the properties of the repaired specimens was studied. Then, the tensile fracture mode of the repaired specimens was analyzed. The results have shown that the repair efficiency of the thin aluminum plate is far higher than that of the thick aluminum plate, and the tensile fracture mode of the repaired specimens has two kinds: the crack growth of the aluminum plate in the repaired specimen and the adhesive debond between the patch and the aluminum plate.