A vehicle brake control system includes an improved ACC system for controlling the operation of a brake actuator and a throttle actuator, based on a signal from a preceding vehicle detector such as a radar device, so that a subject vehicle tracks a preceding vehicle. After a regular brake device is actuated to stop the subject vehicle, an EPB ECU disengages the regular braking device and, instead, actuates an electrically initiated and mechanically maintained parking brake device, so as to temporarily maintain the subject vehicle in a stationary state. Once the electric parking brake device is initiated, its braking state is mechanically maintained even if the flow of current is cut off. Therefore, neither the regular brake device nor the electric parking device consume power while the vehicle is in a stationary state, thereby saving power and minimizing electrical heat generation.