The tribological properties of dialkyldithiocarbamic complexes of molybdenum of different structure have been studied, and their high antiwear, antiscuff and antifriction activity has been established. A specific feature of the complexes studied is that, in the region of extremely low concentrations in hydrocarbon media and at increased (up to 150 degrees C) temperatures, they exhbit useful tribological properties. By X-ray electron spectroscopy it has been found that, when hydrocarbon oil containing molybdenum complexes is used, as a result of tribological contact, protective layers, including molybdenum disulphide and sulphur, arise on the surface of the metal.