In an optical device, a movable unit includes a main body portion, a frame portion that surrounds the main body portion with a predetermined interval from the main body portion, and a plurality of connection portions which connect the main body portion and the frame portion to each other. A width of each of the connection portions is larger than an interval between the main body portion and the frame portion, and is smaller than a distance from a connection position with each of the connection portions in the frame portion to any of a connection position with each of a pair of first torsion support portions and a connection position with each of a pair of second torsion support portions.