A piezoelectric actuator which is capable of reduction of noise resulting from vibration of a piezoelectric element, a piezoelectric vibration device, and a portable terminal are provided. A piezoelectric actuator includes a piezoelectric element including a stacked body composed of internal electrodes and piezoelectric layers which are laminated, and a surface electrode disposed on one of main surfaces of the stacked body so as to be electrically connected to the internal electrodes; a flexible substrate electrically connected to the surface electrode; and a shock-absorbing material disposed on the flexible substrate. The shock-absorbing material, at least partly, is disposed on a first region of the flexible substrate which overlaps with the piezoelectric element.