On the basis of distribution dependences, an analysis of the effect of the macrocomponent (lanthanide) on the extraction of the microcomponent (americium) by benzyl-dialkylamines and benzyltrialkylammonium salts has been made. Assuming the validity of DLn=f(c
) and DAm=f(c
), the power function of the general expression log D=logP-Qlog c
has been calculated, the constants have been determination of the equation applying to individual extraction systems and their physical and chemical characteristics have been discussed.