Roots vacuum pump (Roots pump for short) is a rotary variable capacity vacuum pump. According to the different working range of Roots vacuum pumps, they are divided into low vacuum Roots pumps that discharge directly to the atmosphere, medium vacuum Roots pumps (also known as mechanical booster pumps) and high vacuum Roots pumps. It is widely used in metallurgy, petrochemical, papermaking, food, and electronics industry sectors.

Since the Roots pump is a vacuum pump without internal compression and usually has a very low compression ratio, high and medium vacuum pumps require a backing pump. The ultimate vacuum of a Roots pump not only depends on the structure and manufacturing accuracy of the pump itself, but also depends on the ultimate vacuum of the backing pump. In order to improve the ultimate vacuum degree of the pump, Roots pumps can be used in series.