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Aiming to meet the energy demand of agriculture micro-type sensor and real-time condition monitoring system, and reduce the pollution of chemical batteries to water and soil, a vortex induced vibration piezoelectric wind harvester was proposed and researched in theory and experiment. The theoretical model of the vortex induced vibration piezoelectric wind harvester was established and the simulation analysis was carried out. The influence of the angle of attack, length of piezoelectric cantilever and wind speed on deformation of piezoelectric cantilever was studied. A prototype of the energy harvester was made and the output voltage of the energy harvester was investigated. The results showed that there were two angles of attack that made the output voltage of the energy harvester larger at each wind speed. The two optimal angles of attack for piezoelectric cantilever lengths of 60mm and 78mm and wind speeds of 7.6m/s, 11.6m/s, and 12.4m/s were (35°,135°), (45°,125°) and (50°,120°) and (35°,120°), (40°,115°) and (45°,110°), respectively. When the angle of attack was 120°, there was an optimal wind speed to maximize the output voltage of the energy harvester. With the increase of length of piezoelectric cantilever, the optimal wind speed was decreased from 12.4m/s to 8.4m/s, and the corresponding maximum output voltage of the energy harvester was increased from 16.6V to 16.8V. When the external resistance was 150kΩ and the wind angle was 30°, the measured maximum output power of the energy harvester was 1mW. Therefore, according to the range of the actual wind speed to determine the reasonable angle of attack and the length of piezoelectric harvester can be helpful for a wind energy harvester to generate more energy.