A novel ZnO nanogenerator (NG) with a flexible and highly lightweight substrate has the potential to harvest energy from human respiration. Previous studies have proposed lift-off and fold-up fabrication methods. The ZnO nanowires (NWs) are transferred to a polydimethylsiloxane (PDMS) layer, which serves as the secondary flexible substrate. The thickness of the 2-fold ZnO NG is approximately 25 μm, whereas the thickness of the 16-fold NG is approximately 200 μm. The 16-fold ZnO NG generates approximately 0.6 V and 0.5 μA at the low air flow rate of 2.0 ms-1, and reaches approximately 1.3 V and 0.8 μA at the air flow rate of 5.0 ms-1.