A vacuum pump comprises a pump case having an interior space, a rotor disposed in the interior space of the pump case, and a thread stator disposed in the interior space of the pump case and opposite to an outer peripheral surface of the rotor. At least one heater is arranged in the thread stator for heating the interior space of the pump case. An output device outputs a parameter constituting a factor for determining a temperature of the rotor. A memory stores a database containing information corresponding to a relationship between the parameter output by the output device and a preselected temperature of the heater. A controller inputs the parameter output by the output device and selects from the database stored in the memory the preselected temperature of the heater in accordance with the input parameter.