A pi-shaped piezoelectric harvester which can be applied for using tension and vibration of cables in cable-stayed bridge and suspension bridge was proposed and the generating output characteristics were studied depending on the ceramic and the elastic body size. The harvester consists of a pi shaped elastic body and a rectangular piezoelectric ceramic which is attached on the upper surface of the elastic body. If contraction and release are given symmetrically at both ends of the elastic body legs, bending of the elastic body and the ceramic plate is occurred and electricity is generated by the piezoelectric effect of the ceramic. Structure of the pi-shaped harvester has advantage to protect the ceramic from direct pressure and vibration and it is easy to change the design by changing the position of the legs and the leg length and thickness. Generating characteristics of the harvester were analyzed by using finite element method program ANSYS. The generating characteristics of the harvester were analyzed depending on the elastic body thickness, ceramic size and the applied forces on the legs. The harvester was fabricated on the basis of the analyzed results and a frequency controllable vibrator was used to measure the output characteristics. The generating output characteristics of a single harvester and arrayed harvesters were measured. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.