In recent years, the study of the biological action of silver nanoparticles, especially their interaction with cell membranes, has been of particular interest. The study of complex systems that simulate cell membranes, the nature of their interaction with silver nanoparticles in different concentrations, as well as the effect of lipolytic enzymes on the resulting complexes is of fundamental and applied importance. We investigated multicomponent systems based on egg phosphatidylcholine and cholesterol in a ratio of 14:1 in the presence of lipase (at a concentration of 1,0 rel.u.) after adding silver nanoparticles (AgNPs) at concentrations from 0,01 to 1,0 rel.u. The appearance in the mixture of a large number of small-diameter AgNPs leads to a sharp decrease in the average particle diameter and a slight decrease in the surface tension (ST) of the system. In our opinion, the decisive importance for reducing the ST is not so much the presence of small particles as their number, which is reflected in the ratio of the values of the average and effective diameters. The most pronounced decrease in the average diameter and an increase in the values of this ratio begin due to the AgNPs addition at a concentration of 0.1 rel.u. A decrease in ST by 0,5 mN/m occurs in the system due to the AgNPs addition at a concentration of 1,0 rel.u.