We fabricate a flexible hybrid nanogenerator (HNG), based on multilayered nanocomposite materials, which integrates a piezoelectric nanogenerator (PENG) and a triboelectric nanogenerator (TENG) into a single structure with only two electrodes. The HNG enables enhancement of the electrical output of the nanogenerators. An open-circuit voltage of 280 V and a short-circuit current of 25 μA are achieved by a HNG of 2.5 cm × 2.5 cm in size, superior to the performance of previously reported HNGs. In addition, the energy-conversion process of the HNG relies on the working mechanism of both the PENG and TENG. The polarization direction and doping content of BTO are the two major factors that affect the electrical output. Biomechanical energy harvesting from walking motion or the bending of an arm is also demonstrated.