[Task] To provide a control device for a walking assistance device that can operate appropriately in dealing with a reflexive action of the user in an unexpected situation such as when tripping over something.[Means to Achieve the Task] The control device for a walking assistance device, the walking assistance device comprising an actuator (TA1, TA2) provided in association with a hip joint and/or a knee joint, and a controller that computes an assist force for the corresponding joint to reduce an effort to flex the corresponding joint and controls the corresponding actuator accordingly, comprises: a sensor (31) for detecting a walking state of the user a determination unit (36) for detecting an abnormal state of walking according to an output signal from the sensor a switching unit for invoking an abnormal mode (40, 41) when an abnormal state of walking is detected by the determination unit whereby the controller controls the actuator in a way different from that under a normal mode (39).
