To provide a vehicle running managing system for automatically deciding a reference pulse of a speed sensor.

A GPS receiver 19 is connected to a running managing meter body 1 carried in a vehicle 2 to calculate a vehicle speed based on position information and time information obtained from a GPS satellite. Then, the speed information obtained by the calculation is compared with an output of a speed sensor 9 provided in the vehicle, thereby obtaining number of reference pulses of the sensor 9.