There is provided a piezoelectric device including a pressure chamber, a piezoelectric element, and a diaphragm disposed between the pressure chamber and the piezoelectric element. The piezoelectric element is disposed on the diaphragm so as to overlap an inner periphery of the pressure chamber in plan view, and has an inner edge on a center side of the pressure chamber with the inner periphery of the pressure chamber being sandwiched within the piezoelectric element in plan view. A shape of the inner edge of the piezoelectric element is such that in the smallest first rectangle, which includes the inner edge in plan view.