The routes of synthesis of polysiloxane xerogels functionalized by nitrogen-, oxygen-, phosphorus- and sulphur content ligand groups were investigated. Applying a number of physical methods (SEM, TEM, AFM, IR and Raman spectroscopy, 1H, 13C, 29Si and 31P CP/MAS NMR spectroscopy, EPR spectroscopy, ERS and thermal analysis) the structure of xerogels and their surface was established. The influence of some factors on the structural-adsorption characteristics of such xerogels and their sorption properties were analysed.