The 5A06 Al alloy samples with preset grooves are repaired by using laser cladding. The microstructures and tensile properties of these repaired samples are investigated by using metallurgical microscopy and scanning electron microscopy. The β phase in the heat affected zone during repair grows as a result of heat input. When the line energy reaches 166.7 J/mm, the β phase size increases to larger than 1 μm. The microstructure of repaired zone is composed of α phase, β phase within α grains, and Al-Si eutectic phase along α phase grain boundary. The lack-of-fusion defects are effectively suppressed when laser power is 1400 W and the pore defects result in the tensile strength and elongation of the repaired zone lower than those of base metal.