An image forming apparatus including: a polygon motor that rotates a reflection member; a laser emitting section that emits a laser beam toward a side face of the rotating reflection member; a photoconductor that is scanned by a laser beam reflected from the side face of the reflection member; a beam detecting section that detects a scanning start position of the reflected laser beam, and a scanning final position; and a control section that controls the polygon motor and the laser emitting section, based on detection signals from the beam detecting section, wherein when the detection signal at the scanning start position does not meet a predetermined time-based standard and/or a predetermined output-level standard, the control section controls the polygon motor so that the reflection member rotates in a reverse direction.