The mechanical properties and microstructure evolution of novel Al-Mg-Zn alloy during quasistatic and dynamic impact processes were investigated by Gleeble-1500, separated Hopkinson pressure bar(SHPB), optical microscope, scan electron microscope and transmission electron microscope. The Al-Mg-Zn alloy exhibited a global strain hardening effect in quasistatic impact. The dynamic yield strength increased first and then decreased slightly with the increase of strain rate. The grains of alloy deformed to different degrees with the change of strain rate, and the grains deformation inhomogeneity became more serious with the increase of strain rate. The morphology, density and size of precipitates varied significantly before and after dynamic impact with 4800s_^-1.