Under displacement load, in order to predict the fatigue life of the folding piezoelectric vibrator due to the thickness of the bonding layer, a theoretical analysis of the bonding layer was carried out and a finite element model of the folding piezoelectric vibrator was established. The sinusoidal displacement loads are applied under three different working modes of 85.5 Hz, 105.8 Hz and 153.2 Hz, and the static analysis of the model was performed. The analysis results were transmitted to the nCode DesignLife software for fatigue analysis. The results show that when the thickness of the adhesive layer was 0.07 mm, the stress values of the elastic layer and the piezoelectric layer were the minimum. From the analysis of fatigue life, the structural damage was concentrated in the piezoelectric ceramic layer. At 105.8 Hz, the fatigue life of the piezoelectric layer was 5.317×107, at 85.5 Hz and 153.2 Hz, the fatigue life of the piezoelectric layer is 8.82×106 and 1.624×106 respectively. Therefore, in the practical application of folded piezoelectric vibrators, it is necessary to comprehensively consider the thickness of the bonding layer, the displacement load and the fatigue life of the piezoelectric ceramics in order to achieve the maximum power output.