To provide a low-cost vacuum pump comprising a single part, having a compact structure, and occupying only a small area in the vacuum pump to cover the whole pressure range from the atmospheric pressure to the high vacuum of approximately 10-4 mbar.

This vacuum pump is formed of two system gas friction pumps 6 and 7 and a pump 8 in its downstream side thereof. The gas flow of the two-system gas friction pumps is collected by a coupling element 26 inside the pump, and compressed to the atmospheric pressure by the pump in the downstream side thereof. The gas friction pumps are favorably formed as a two-system Holweck pump and the pump in the downstream side is formed of a side channel pump. The compact structure of the pump is complemented by a stator element 15 of the side channel pump comprising a non-divided disk.