Abstract: This paper investigates 5182 aluminium alloy clinched joints during fatigue service. The inherent frequency of the joints was collected in stages by alternating dynamic response-strength degradation tests and the residual static strength of the joints was tested during fatigue service. The failure process of fatigue degradation of clinched joints was investigated and quantified with the help of inherent frequency variation and strength degradation laws. Quantification of joint service failure was explored based on residual strength nonlinear theoretical model and cumulative damage model. The test results show that the inherent frequency curve of the clinched joints during fatigue loading shows a significant left shift phenomenon. As the inherent frequency of the joint decreases with the increase of service life, the residual strength of the joint also shows a corresponding decrease. The inherent frequency decline curve and the strength degradation curve have roughly the same trend, and the change stage partition is obvious, both showing the process from a gentle decrease to a sharp decline. Based on the two models, a theoretical formula for the fatigue service strength degradation of clinched joints is established, and a prediction model for the residual strength of 5182 aluminium alloy clinched joints is further derived, which is empirically proved to have good application effect.