The invention discloses a continuous driving mileage calculation control system and a calculation control method. The calculation control system comprises an MCU microprocessor, a continuous driving mileage digital display, a vehicle speed signal sampling circuit, an instantaneous fuel consumption signal sampling circuit and a fuel signal sampling circuit. According to the received instantaneous fuel consumption signal and the vehicle speed signal, the MCU microprocessor calculates the average fuel consumption, and then calculates the continuous driving mileage according to the average fuel consumption and the current remaining fuel amount. The digital display is used for displaying the continuous driving mileage. The average fuel consumption refers to the amount of fuel consumption per hundred kilometers between two refilling; and the remaining fuel amount is obtained by deducting the amount of fuel consumption calculated according to the instantaneous fuel consumption signal from the amount of remaining fuel amount measured right after the refilling.