The deflecting mirror includes a fixed base member; a mirror having a reflection surface; a support member swingablly supporting the mirror; a pair of driving beam members, each having a first end connected with the fixed base member and a second end connected with the support member to support the support member from both sides; and a piezoelectric member fixed to each driving beam member and extending from the first or second end of each driving beam member while having length not longer than about half the length of the driving beam member. The piezoelectric member and the driving beam members constitute piezoelectric unimorph or bimorph structure. By applying voltage to the piezoelectric member, the driving beam members are driven at the same time in the same direction, thereby vibrating the support member in a direction perpendicular to the reflection surface of the mirror, resulting in swinging of the mirror.