Essential sorts of disinfecting agents and principles of their action have been considered in the paper. Results of research on application of washing-disinfecting liquids, containing silver nano-particles, in meat industry have been presented. It has been established that liquids characterized by very efficient bactericidal and fungicidal properties can be prepared by composition of toxieal ly performing silver nano-particles, some degreasing agents, reducing surface tension, and frothing agents. The listed components eliminate "insulating effect" of fat particles in which bacteria are suspended and facilitate silver nano-particle contact with bacteria and fungi, increasing this way biochemical effect of silver nano-particles.