Water is essential ingredient of all living organisms. It is vital and irreplaceable as food and feed, as the subject and mean of the work in many industrial branches, agriculture, forestry and fishery and for environmental preservation. It is very important for potable water to ensure its quality especially regarding organoleptic and microbiological parameters. Water disinfection procedures plays unavoidable role. Different methods for water disinfection, based on chemical or physical techniques, are widely applied today. The objective of this bachelor graduate thesis was to obtain hypochlorous acid by the mean of electrolysis, thus enabling in situ application of it for water disinfection. Electrodes of the type 1A, 4A and 10A were used as anodes, and graphite electrode as cathode. Electrolysis was performed in two combinations of electrolyte. In the first one water solution of sodium chloride was used as catholyte, and distilled water as anolyte. In the second one sodium chloride solution was in both spaces of electrolytic cell. Products obtained by electrolysis in anodic space of the cell were investigated by the use of cyclic voltammetry. On the basis of the obtained cyclic voltammograms it was concluded that in the experiments in which in the cathodic space of the membrane electrochemical cell solution of sodium chloride was charged and in anodic space distilled water, by the application of any electrode between 1A, 4A or 10A hypochlorous acid was obtained. In the experiments in which in both anodic and cathodic spaces water solution of sodium chloride was charged, by the use of any electrode between 1A, 4A and 10A, no hypochlorous acid was obtained. It was concluded on the basis of the obtained cyclic voltammograms, as well. By the comparison with literature data it was found that curves of cyclic voltammograms are characteristic for sodium chloride solution. In further research the influence of the process parameters at reactant conversion should be studied. Efficiency of the obtained hypochlorous acid in situ as water disinfectant should be studied, as well.