A motor controller is provided with a velocity processing unit that determines a corrected target rotation velocity by correcting the inputted target rotation velocity of the motor in accordance with a velocity deviation between the inputted target rotation velocity and an actual rotation velocity detected from the motor, a first PWM circuit that repeatedly outputs an on-signal having a first pulse width at a first carrier frequency, wherein the first pulse width of the on-signal is modulated by the first PWM circuit in accordance with the corrected target rotation velocity, a second PWM circuit that repeatedly outputs an on-signal having a second pulse width at a second carrier frequency, wherein the second pulse width is different from the first pulse width, the second carrier frequency is lower than the first carrier frequency, and the second pulse width of the on-signal is modulated by the second PWM circuit in accordance with the corrected target rotation velocity, an AND circuit that receives the on-signal outputted from the first PWM circuit and the on-signal outputted from the second PWM circuit and outputs third on-signal which is a logical product of the on-signals, and a voltage apply circuit that applies voltage to the motor intermittently in synchronization with the third on-signal outputted from the AND circuit. As a result, the rotation velocity of the motor may be correctly controlled.