Oligomer guanidines are highly efficient biocides against a broad spectrum of microorganisms. However, their stimulatory effects have not been studied yet. Our data allow us to expect the presence of growing stimulatory action for polyhexamethyleneguanidine (PHMG) under determined conditions. We investigated the action of the member of the polyguanidine family of biocides, PHMG on seeds growing. The comparative analysis of PHMG action was carried out on seeds of wheat, pea, rye, beet and maize. It was shown that of all PHMG salts tested only PHMG chloride and PHMG succinate could stimulate the growing of seeds. PHMG was also capable to increase their germination and vigor. The action on seeds of PHMG mixtures with inorganic salts (microelements) has also been examined. Amongst the drugs tested with a wide variety of ingredients the best stimulatory properties were proven for the composition of PHMG and succinic acid with boron, zinc, cobalt and magnesium. Most efficient growth stimulation was achieved after 15-minutes pre-sowing soaking of seeds of peas and beets. The stimulatory concentrations of PHMG were falling within the range of 0.001 to 0.5 %. Thus, the salts of PHMG can either depress or stimulate living organisms (including seeds) depending on PHMG concentration and anionic composition. The stimulation can be achieved by the non-specific adaptation of the cells (stress). In this case the stimulation is determined by the changes in the plasma membrane of the cell after adsorption of PHMG. The polycation of PHMG binds strongly with phosphoglycerides. Some lipids withdraw from participation in cellular processes. The acceleration the of new lipids synthesis and membrane-bound enzymes is likely to occure in the cell. The acceleration of new lipids synthesis and membrane-bound enzymes is likely to occur in the cell.