Quench sensitivity relative to exfoliation corrosion of 7085 aluminum alloy plate was investigated by means of end-quench test, corrosion immersion test, scanning electron microscopy(SEM), transmission electron microscopy (TEM). The results show that the resistance to exfoliation corrosion of 7085 aluminum alloy plate decreased with quench rate decreasing, from EA to EB and the maximum corrosion depth from 135 μm increasing to 315 μm, there is a liner relation between the corrosion depth and the logarithm of quench rate. With decrease of quench rate, the size of η equilibrium phase at grain boundaries increased, wider precipitate free zone near grain boundaries and some equilibrium η phase precipitate at sub-grain are primarily responsible for quench sensitivity relative to exfoliation corrosion.