A mass flow controller and mass flow meter are disclosed. The mass flow controller and mass flow meter include a sensor tube configured to transport a fluid, and an upstream heater element and a downstream heater element which are formed of heating resistance wires provided in an outer periphery of the sensor tube. At least one weld terminal is electrically connected to an end of one or more of the heating resistance wires by spot welding material. A temperature difference between the melting point of the weld terminal and a melting point of the heating resistance wires does not exceed 100 degrees Celsius, and one or more coat layer(s) is provided on a surface of the weld terminal.