In order to automatically adjust a self-bias on a substrate to a constant value at all times and to form a high-quality insulating film with excellent process reproducibility, a vacuum thin film forming apparatus according to the present invention includes: a high-frequency sputtering device having a chamber, an evacuation means for evacuating the inside of the chamber, a gas introduction means for supplying gas into the chamber, a substrate holder provided within the chamber, and an electrode provided within the substrate holder; and at least one vacuum treatment chamber that can be selected from a group including a physical vapor deposition (PVD) chamber, a chemical vapor deposition (CVD) chamber, a physical etching chamber, a chemical etching chamber, a substrate heating chamber, a substrate cooling chamber, an oxidation treatment chamber, a reduction treatment chamber, and an ashing chamber, wherein the high-frequency sputtering device further includes a variable impedance mechanism electrically connected to the electrode for adjusting the potential of the substrate on the substrate holder.