A body-worn motion assisting device (1) comprises a shoulder joint mechanism (5) for assisting the user to move a shoulder joint, an elbow joint mechanism (6) for assisting the user to move an elbow joint, and a control unit (100) having a control circuit for controlling a drive unit (11) of the shoulder joint mechanism (5) and an elbow joint mechanism (6). The control unit (100) controls the drive unit (11) according to the physical quantities and biosignal detected by an angle sensor, a torque sensor, and a biosignal sensor. A control section of the drive unit (11) includes a motor monitoring block for monitoring the operation state of a motor and a motor control block for limiting the drive signal sent to the motor depending on the results of monitoring by the motor monitoring block so that the motor does not become under overload.
