An effect of aqueous subphases composition on the character of change of the bilayer structure of malonate mono and dinitroxyl methanofullerenes surface films has been estab lished. Their transformation to monolayers takes place in the presence of hydroxy containing compounds (quercetin, dihydroquercetin, 4 methylphenol, ascorbic acid, as well as in a buffer mixture with рH 10). A loosening of mixed films on the basis of nitroxyl methanofullerenes in the presence of compounds affecting radical processes (2,4,6 tri(tert butyl)phenol, 2 methyl 3 nitrosopropane, and ТEМРO) has been demonstrated. The character of compression isotherms π = f(А 0 ) (π is a surface pressure, A 0 is an effective molecular area of methanofullerene) of the mixed films on water depends on the nature of component incorporated and the reaction time in solution: in all the cases, А 0 increased almost 2 fold, to 1.05 nm 2 molecule -1 , whereas a com pressibility parameter β decreased 2-3 fold, to (1-2)•10 17 N m -3 . Visualization of the thin film surfaces (atomic force spectroscopy) showed that a decrease of parameter β in the Langmuir layers corresponds to the particle aggregation and structurization of the films.