In order to provide a stable, efficient and long-term energy supply method for wireless sensor network nodes, a piezoelectric energy harvesting interface circuit based on an enhanced synchronous charge extraction circuit(ESECE) is proposed. The enhanced synchronous charge extraction circuit is simulated by using the Multisim circuit simulation software, and compared with the standard piezoelectric energy harvesting interface circuit(SEH) and the synchronous charge extraction circuit(SECE).The experimental results show that under the same excitation conditions, the output power of the ESECE is nearly 30% higher than that of the SECE,the maximum output power of the ESECE is up to 190 μW.At the same time, it guarantees the independence of the output power and the load resistance.