Abstract: With the development of China’s smart grid and the expansion of grid scale, piezoelectric material based sensors and energy harvesters are playing an increasingly important role in online monitoring, troubleshooting and wireless sensor network. In this article, from the perspective of grid monitoring and self-powered sensors, an investigation is conducted on the recent research progress of voltage and electric field sensors, acoustic detection and environmental energy harvesters, and an introduction is also made to the traditional and newly-emerged piezoelectric materials such as inorganic piezoelectric ceramics, piezoelectrets, and piezoelectric composites. On the basis of current researches, the challenges encountered in the field of piezoelectric devices for smart power systems are pointed out, including frequency matching, environment stability and integration, etc. The practical application of new piezoelectric devices will need the assistance of emerging nano processing technologies, exploring the coupling effect of piezoelectric effect and other physical effects, designing new piezoelectric materials and energy harvesting circuits.