A piezoelectric/electrostrictive device is disclosed comprising a driving portion to be driven by a displacement of a piezoelectric/electrostrictive element, a movable portion to be operated by a drive of the driving portion, a fixing portion for holding the driving portion and the movable portion, the movable portion being coupled with the fixing portion via the driving portion, and a hole formed by inner walls of the driving portion, an inner wall of the movable portion, and an inner wall of the fixing portion. The driving portion comprises a pair of mutually opposing thin plate portions, and a piezoelectric/electrostrictive element including a piezoelectric/electrostrictive operating portion comprising at least a pair or more of electrodes and a piezoelectric/electrostrictive layer formed on at least a part of the outer surface of at least one thin plate portion out of the thin plate portions, one end of the piezoelectric/electrostrictive operating portion in a direction in which the fixing portion is connected with the movable portion exists on the fixing portion or the movable portion, and the other end of the piezoelectric/electrostrictive operating portion is arranged on the thin plate portion, and at least a piezoelectric/electrostrictive layer of the piezoelectric/electrostrictive element exists extending over the movable portion and the fixing portion. The device of the present invention, having high rigidity in the width direction of the thin plate portions, namely in the Y-axis direction, enables rigid joining when functional parts such as sensors, magnetic heads, or the like are fixed to the present device, and further when the present device per se is fixed to another structure.