The utility model provides a water electrolytic hydrogen production electrolytic device, including the electrolysis trough, the outside cover of electrolysis trough has the drum, be equipped with the oxygen outlet duct in the cavity between drum and the electrolysis trough, be connected with the hydrogen outlet duct on the electrolysis trough, the hydrogen of electrolysis trough output comes out directly to get into through the hydrogen outlet duct and uses the workshop, the oxygen of electrolysis trough output passes through oxygen air balance pipe no. 1 and gets into in the catch water, detach vapor and water in the oxygen, oxygen behind the dewatering passes through in the cavity between oxygen air balance two reentrant drums of pipe and the electrolysis trough, discharge through the oxygen outlet duct at last, the utility model discloses a sealing technique problem inadequately of pressurized -water electrolytic hydrogen production electrolysis trough in present has been solved in order to regard as balanced gaseous mode from balanced structure and oxygen.