In this work, a bridge-type piezoelectric energy harvester combined with proof masses that can work at high acceleration was designed, simulated, and fabricated. The energy harvester was achieved by bonding bulk Pb[ZrxTi1−x]O3 (PZT) onto a flexible phosphor bronze substrate by a low-temperature process, and an additional tungsten mass was assembled at the center of the bridge top surface to reduce the resonant frequency of the harvester. The device has good flexibility and is operable under high-acceleration conditions. The experimental results showed that at the resonant frequency, which is 511 Hz, the maximum open-circuit voltage is 4.72 V, when the input vibration acceleration is 8g. The maximum output power and output power density under 8g are 56.74 μW and 721.286 μW/cm3, respectively. Additionally, we applied the fabricated device on a vacuum compression pump to test the output voltage, and found the maximum output voltage to be 0.34 V.