Provided is a conveyor belt wear monitoring system capable of determining the wear condition of an upper rubber cover of a conveyor belt. When the conveyor belt is stopped, on the return side of the conveyor belt, a wear detector with a sensor unit corresponding to an upper cover rubber is disposed, the wear detector is controlled by a control unit to move across an entire length in a belt width direction and the distance from the sensor unit and a surface of the upper cover rubber is detected, the detected data is received by a calculation unit, and an amount of wear of the upper cover rubber is calculated on the basis of the received data.