A novel wind-induced-vibration piezoelectric-energy harvester with a deformable airfoil-shaped bluff body is proposed in this study to solve the problems of narrow wind speed bandwidths and excessive amplitudes at high wind speeds. The harvester mainly consists of a deformable bluff body， cantilever beam， and piezoelectric vibrator. The elastic wing of the bluff body deforms at different wind speeds， thus achieving the self-adjustment of the vibration characteristics and improving the environmental adaptability of the harvester. A COMSOL finite element model of the energy harvester is established， and the effect of wind speed on the shape and vibration characteristics of the bluff body is analyzed via simulations and experiments. In addition， the effects of windward angle θ and elastic wing thickness e on the output performance of the energy harvester are determined. The results show that the wind speed bandwidth of the harvester ranges from 4 m/s to 25 m/s at a windward angle θ of 120° and an elastic wing thickness e of 0.15 mm. Furthermore， the deformation of the elastic wing becomes small when the wind speed is lower than 8 m/s. When the wind speed ranges from 8 m/s to 17 m/s， the harvester experiences a transformation from galloping to vortex-induced vibration， resulting in a decrease in the output voltage. When the wind speed ranges between 17 m/s and 25 m/s， the bluff body has an arc shape because of the excessive deformation of the elastic wing. The harvester is dominated by vortex-induced vibration， and thus， its amplitude can be effectively suppressed. The output voltage decreases with increasing wind speed. Additionally， the test results show that the harvester can yield a maximum output power of 3.78 mW at a matching impedance of 250 kΩ. Both the theoretical analysis and experimental results indicate that the proposed harvester can satisfy the requirements of high reliability， low cut-in wind speed， and broad wind speed bandwidth， as well as generate considerable electric power.