A novel hybrid energy harvester integrated with piezoelectric and electromagnetic mechanism is designed for powering wireless sensornodes in smart grid. In the proposed energy harvester device, four permanent magnets are attached on a piezoelectric cantilever array,and a Printed circuit board (PCB) with induction coils is mounted surrounding the magnets. The magnets couple to magnetic field ofAlternating current (AC) carrying conductor and excite the piezoelectric cantilever array. Vibration energy is converted to electric energyvia both piezoelectric and electromagnetic transduction mechanisms. A prototype in volume of 50×50×12 mm3 was fabricated and tested. From current-carrying conductor of 2.5A at 50 Hz, the proposed energy harvester combined with piezoelectric components and electromagneticelements can generate up to 295.3 μW and 46.6 μW, respectively. With the total output power of 341.9 μW, the power densityis much higher than the one generated only by conventional piezoelectric energy harvester under the same condition.