Abstract: The effects of artificial ageing on the microstructure and mechanical properties and intergranular corrosion properties of 6005A alloy containing Sc were investigated by tensile testing, intergranular corrosion testing, metallography, scanning electron micrography and transmission electron micrography.The results show that the addition of Sc can effectively improve the tensile properties (tensile strengths, yield strengths and elongation up to 366 MPa, 334 MPa and 15.4%, respectively)of the peak-aged 6005A alloy, and the scanned fractures show plastic fracture characteristics.At the beginning of aging, the intergranular corrosion susceptibility increases with increasing aging time until the peak aging intergranular corrosion susceptibility reaches its maximum, and then the intergranular corrosion susceptibility decreases.