A motor-assisted bicycle (10A through 10E) includes an assistive motor (66) for generating a drive force to assist in a pedalling force applied by a rider to pedals (52L, 52R), a battery module (128, 240, 282, 312) including batteries (142) as a power supply for the assistive motor (66), and an alarm buzzer (22) mounted in the battery module (128, 240, 282, 312). An alarm sound generated by the alarm buzzer (22) is emitted in a forward direction of the motor-assisted bicycle. Thus, a rider of the motor-assisted bicycle can seek attention of people walking in the vicinity of the bicycle by producing an alarm sound.