VEHICLE CONTROL SYSTEM

PROBLEM TO BE SOLVED: To provide a vehicle control system capable of more strictly determining whether or not a portable machine is located in an effective area by following the using way of the portable machine.SOLUTION: In a vehicle control system: for example, a portable machine performs an area determination on the basis of the reception strength of a radio signal (vehicle signal) transmitted from an on-vehicle machine (S190); and when the portable machine determines that it is located in an effective area (S190; YES), it notifies the on-vehicle machine of this fact by a radio signal (determination signal) (S200). For example, such a vehicle control system is configured so that: when the portable machine performs the area determination, the reception intensity of a vehicle signal is compensated according to the decrease of receiving sensitivity of the portable machine different according to the using way of the portable machine, such as an orientation (inclined quantity) of the portable machine 10 and the residual quantity of a battery when receiving the vehicle signal (S180).