To provide a failure detector for a yawrate sensor capable of completely preventing the erroneous detection of the yawrate sensor during sports running or if the possibility of the sports running is high.

This failure detector for the yawrate sensor, which determines it as the yawrate sensor having some failure if a state where a yawrate sensor value of the yawrate sensor for detecting a yawrate of a vehicle is in excess of a predetermined failure determination threshold continues for over a failure determination detection time, takes any of the following means at the time of determining the sports running state or stopping a vehicle behavior controller: (1)prohibiting the failure detection of the yawrate sensor, (2)changing the failure determination threshold to a larger value than normal value, and (3)changing yawrate sensor failure determination detection time to a longer time than normal time.