This optical scanning device includes: a shaft part to which a mirror part is connected; a movable magnet; a base part; a ball bearing; a core unit that has a core body and a coil body and rotationally drives the movable magnet; and a magnet position holding member that is a magnetic body provided facing the movable magnet and magnetically attracts the movable magnet to a reference position. The core unit is disposed on the outer surface side of one wall section of a pair of wall sections of the base part. An angle sensor unit for detecting the rotation angle position of the shaft part is disposed between the core unit and the one wall section.