The invention provides a circular flux trajectory control device and a circular flux trajectory control method based on a regular dodecagon. The circular flux trajectory control device comprises a vehicle-mounted power battery, an auxiliary power supply, a main controller, a driving circuit, a three-phase permanent magnet synchronous motor, a power tube unit, a first relay, a second relay and a third relay, wherein the effect of controlling a flux trajectory of the three-phase permanent magnet synchronous motor is realized through controlling switching tubes of the power tube unit by means of the main controller. During the control process, the control of the flux trajectory of the three-phase permanent magnet synchronous motor is realized through controlling the switching tubes of the power tube unit directly, complex links such as vector transformation are not needed, the control process is simple, and the response speed of the three-phase permanent magnet synchronous motor is increased.