There are provided a piezoelectric actuator having reduced noise caused by the vibration of a piezoelectric element is reduced, a piezoelectric vibration apparatus and a portable terminal. A piezoelectric actuator includes a piezoelectric element which includes a stacked body in which internal electrodes and piezoelectric layers are laminated, and a surface electrode disposed on one main surface of the stacked body so as to be electrically connected to the internal electrodes; and a flexible substrate electrically joined to the surface electrode; and a reinforcing plate fixedly attached to a region of the flexible substrate where the flexible substrate overlaps with the piezoelectric element, the reinforcing plate being provided with a bend portion.