X ray diffraction, thermal analysis and electrochemical analysis were used to study the disproportionation behaviour of LaNi 5- x M x in hydriding process at high temperature and the electrochemical properties of the reaction products. The results prove that the disproportionation takes place and the precipetated nano phase metallic nickel is formed at a certain temperature and time. The extent of the disproportionation reaction is closely related to temperature, heating time, substituted metal and the heat of formation of the alloys. Measurement of the exchange current density shows that the nano phase contained nickel composite structure obtained by the disproportionation reaction are better in electrocatalytic characteristics than the master alloys.