The effect of pre-deformation amount on microstructure and properties of Al-Zn-Mg-Cu aluminum alloy was studied by hardness and electrical conductivity, tensile test, intergranular corrosion and exfoliation corrosion experiments, optical microscopy （OM），scanning electron microscopy（SEM） and transmission electron microscopy（TEM）. The results showed that the strength of the alloys with the increase of deformation amount first increased and then decreased under the same ageing heat treatment. The tensile strength and yield strength of the alloy with pre-deformation amount of 5.8% was 577.8 MPa and 549.8 MPa，respectively, which was increased by 25.7% and 20.8%，respectively，when compared with those without pre-deformation. The corrosion resistance was improved with the increase of pre-deformation. The precipitates became the larger discontinuous distribution grain boundary one and the width of the precipitate free zone became wider，which were attributed to the pre-deformation resulting in a large number of dislocation and benefit for precipitation under re-ageing．