The subject of the invention is a method and device for reducing contamination in a plasma reactor, especially contamination by lubricants, particularly for plasma processing of materials. The method is based on the fact that the contaminated gas pumped out of at least one reduced pressure vacuum chamber in the form of a plasma lamp (LA1, LA2, LA3) is purified in at least one purifying plasma lamp (LA01, LA02, LAH, LAE), in which a glow discharge is initiated between the anodes of the purifying plasma lamp (A01, A02) and the cathodes of the purifying plasma lamp (K01, K02), favorably particles of lubricants are cracked and partially polymerized, while processed heavy particles of lubricants are collected in a buffer tank (ZB) and then discharged outside the pumping system. The device contains at least one reduced pressure vacuum chamber in the form of a plasma lamp (LA1, LA2, LA3), it is connected to at least one purifying plasma lamp (LA01, LA02, LAH, LAE) with a buffer tank (ZB) connected to a vacuum pump (PP). The vacuum tube connecting the plasma lamps (LA1, LA2, LA3) with the purifying plasma lamp (LA01, LA02, LAH, LAE)) is equipped with a dosing valve (V) for the gaseous admixture medium (MD) to plasma lamps (LA1, LA2, LA3), from which radiation (R1, R2, R3) is directed to the processed material (OM).