This article deals mainly with the influence of sheet thickness on the fatigue behavior and fretting of single-lap self-piercing riveted joints in aluminum alloy 5052. The fatigue lives, failure modes, failure positions, fretting and fretting failure mechanism of the joints were investigated. A statistical analysis was performed to analyze the rationality of fatigue test data. The results showed that the fatigue life of the joints increases with increasing sheet thickness, but the increase of the fatigue life is limited. And, with increasing sheet thickness the fatigue failure positions transferred from the pierced sheet to the locked sheet. In all the joints fretting resulted in the initiation and propagation of fatigue cracks at the interfaces. Increasing sheet thickness could decrease the size and degree of fretting at the interface between the two riveted sheets.