A vehicle stability control device is mounted on a vehicle in which a front tire wears faster than a rear tire. Understeer degree increases as a target yaw rate becomes higher than an actual yaw rate. When the understeer degree exceeds a first activation threshold, vehicle stability control is activated. When the understeer degree exceeds a second activation threshold, rear brake control that applies a braking force to an inner rear wheel is activated. A wear degree parameter is wear degree of the front tire or a difference in wear degree between the front tire and the rear tire. In response to a fact that the wear degree parameter exceeds a first wear threshold, the vehicle stability control device performs rear wear promotion processing that changes the second activation threshold to an adjusted value smaller than a default value and the first activation threshold.