A vehicle control system executes vehicle stability control and driving assist control. The vehicle control system calculates an unstable state quantity representing instability of the vehicle and an activation threshold of the vehicle stability control, based on a vehicle state detected by a sensor installed on the vehicle. A state change amount is an amount of increase in the unstable state quantity from an average unstable state quantity that is obtained when a lateral acceleration of the vehicle is within a predetermined range. A threshold change amount is an amount of increase in the activation threshold from an average activation threshold that is obtained when the lateral acceleration is within the predetermined range. When the driving assist control is in execution, the vehicle control system activates the vehicle stability control in response to the state change amount becoming larger than the threshold change amount.