Abstract: A speed control method for a brushless DC (BLDC) motor capable of solving the phases distortion problem generated between an applied voltage and a winding current of the motor during a high speed rotation of the motor. According to the method, the present revolution per minute (RPM) of the motor is detected, and an output control wave of a new pattern is obtained utilizing a value of an advance phase angle determined according to the detected RPM of the motor. Accordingly, the rotation of the motor is controlled by the new pattern control wave in response to the motor rotation of a high, intermediate or low speed, and thus the phase distortion generated between the applied voltage and the winding current of the motor can be prevented, resulting in the improvement of the motor efficiency. The method may be applied to a typical sensorless BLDC motor.