Abstract: 7055-T7751 aluminum alloy pre-stretching plate (pre-strains of 1%-3%) was subjected to vibratory stress relief treatment, and then to fatigue tests under different maximum stresses (300, 350, 400, 500 MPa). The effects of vibratory stress relief treatment on microstructure, microhardness, surface residual stress and fatigue property of the alloy were studied. The results show that the vibratory stress relief treatment had little effect on the microstructure and microhardness; the microstructure after vibratory stress relief was still the texture orientation structure of the rolled plate. After the vibratory stress relief treatment, the longitudinal and transverse residual tensile stresses in the alloy were obviously relaxed, and the longitudinal residual stress distribution was homogenized. The vibratory stress relief treatment improved the fatigue performance of the longitudinal and transverse specimens significantly. Under the maximum stress of 350 MPa, the fatigue lives of the longitudinal and transverse specimens increased by 219.0% and 29.1%, and the fatigue limits were improved by 9.9% and 5.1%, respectively.