A piezoelectric device comprises a pressure chamber forming layer, a vibration plate disposed on and connected with the pressure chamber forming layer to form a pressure chamber, and a piezoelectric element disposed on the vibration plate and used for driving the vibration plate to move and thus changing a volume of the pressure chamber, wherein the piezoelectric element is disposed on the vibration plate in such a manner as to cover a portion of the pressure chamber, the piezoelectric element has two opposite ends respectively extending beyond an edge of the pressure chamber and covering the pressure chamber forming layer. The piezoelectric device of the present invention can efficiently actuate the vibration plate, eliminate undesired displacements of the vibration plate in the opposite direction at the edge of the chamber, and provide higher displacement sensitivity to driving voltage.