Using fluorescent probe 4-(n-dimethylaminostyryl)-1-methylpyridinium n-toluenesulfonate the radiation effect on the structure of liposomes composed of phosphatidylcholine and diphosphatidylgycerol has been investigated. The from of fluorescence spectra was analyzed and inhomogeneous broadening parameters of spectral components were estimated. The polarity of DSM environment and probe distribution between different sites were found to change after irradiation.