PURPOSE: To provide the thin film forming device which enables the execution of plural different thin film forming stages, simplifies the construction of a vacuum generator, etc., can efficiently make operations and produces less dust.

CONSTITUTION: Treating chambers 10 having opening surfaces 12 at one end and internally having thin film forming means 14 are fixed and installed at plural points on the circumference. A substrate holder 20 rotating around the center of the entire part of the treating chambers 10 is provided to face the opening surfaces 12 of the respective treating chambers 10. Plural treating substrates 30 can be mounted on the substrate holder 20 on the same circumference as the circumference of the treating chambers 10 on the plane opposite to the treating chambers 10 so that the opening surfaces 12 of the respective treating chambers 10 can be substantially closed by the substrate holder 20.