The filling machine is used for the trade settlement of the filling station filling equipment, its computer control part adopts the high performance industrial control microprocessor chip, in the harsh working environment can still maintain a high stability. The high precision mass flowmeter is selected as the core component of measurement. It has built-in temperature sensor to realize temperature compensation, so that the filling machine can accurately measure. The electrical part adopts explosion-proof structure to adapt to the (explosive) environment of the gas filling station, and obtains the overall explosion-proof certificate to ensure the safety and reliability of the filling machine.