A myoelectric sensor for detecting myoelectric signals which accompany body movement includes: a wearing band that is elastic, expandable, and circular, and that is worn around a limb to surround the limb tightly; myoelectric detection units a plurality of which are disposed in the circumferential direction on the wearing band with intervals therebetween so as to cause each of a plurality of myoelectric detection electrodes to be in close contact with the surface of the limb, and which detect myoelectric signals from corresponding positions on the limb using the myoelectric detection electrodes; and connection cables that electrically connect mutually adjacent myoelectric detection units and thereby transmit the myoelectric signals. The connection cables each include a bent portion, the bent shape of which changes in response to changes in the distance between the mutually adjacent myoelectric detection units.