© The Institution of Engineering and Technology 2019. This Letter presents a radio-frequency energy storage solution for monitoring corrosion on bridge in wireless sensor network system. In this monitoring system, wireless terminals and sensors are installed on the bridges to monitor surface corrosion remotely. The proposed energy storage module to supply power to the sensors consists of a rectifier, a supercapacitor, and a DC-DC boost converter. The rectifier circuit is designed to convert 920 MHz RF energy to DC source. Experimental results demonstrate that the harvested energy can power up the sensor nodes for several times in a week, at input power density of 0.81 μW/cm2.