According to an embodiment, an image forming apparatus includes a motor of which driving current value changes according to a load, an image forming unit, a measuring unit, and a setting unit. The measuring unit forms an image on a medium by using a rotation body rotated by a motor. The measuring unit measures the driving current value of the motor. When a rotation speed of the motor is set to a first speed, the setting unit continues to set the first speed if the driving current value measured by the measuring unit falls within a first range. The setting unit sets a second speed lower than the first speed as the rotation speed if the driving current value measured by the measuring unit falls within a second range higher than the first range.