Abstract: Hydrogen will be one of the most potential energy in the future mainly due to its cleanliness, renewablility and non-polluting nature.At present,the hydrogen-producing ability of bacteria is low, which is one of key factors restricting the development of fermentative hydrogen production industry.Ultraviolet ray was used to mutate a wild hydrogen-producing strain,Ethanoligenens sp.ZGX4, in order to screen highly efficient H2-producing mutants.After investigating the hydrogen production stability of successive generations, a highly efficient hydrogen-producing mutant UV-d48 was obtained,and batch tests were conducted to investigate the H2-producing behavior of mutant UV-d48.The experiment results showed that UV-d48 had H2-producing capability of 2998.5 ml·L-1 and maximal H2 production rate of 34.4 mmol·(g drycell)-1·h-1 at 37℃,initial glucose concentration of 10 g·L-1 and pH of 6.0, which were higher by 65.1% and 56.4% than that of the wild parent strain ZGX4, respectively.Moreover, its hydrogen yield was estimated to be 2.61 mol H2·(mol glucose)-1, which was 1.54-fold higher than that of the control strain ZGX4.Since mutant UV-d48 performed typical ethanol-type fermentation in the course of H2 production, it might be used as a very important carrier material to investigate the metabolic pathway and mechanism of ethanol-type fermentation bacteria.