Numerous data confirm the high effect of electrochemically activated water application in agriculture. Nevertheless, the mechanisms of such effect are still not described in detail. The author studied the influence of preplant treatment of amaranth seeds by electrochemically activated water on activity of respiratory enzymes, the substrates content, the germination energy and the growth strength. It was established, that physico-chemical changes of water after electrolysis induce in seeds different metabolic processes. High content of soluble sugars on the background of anaerobiosis in variants with mixture cathodic and anodic liquors and catholyte only promotes to glycolytic process, but accumulated metabolite pool permit to use them in more various chemical conversions. The increased content of hormones accelerates the growth processes, determines enhanced division and cell distension, the intensive course of initial stages of plant development (increase of germination energy and growth strength in seeds).