Abstract: The acetic acid resolution course is the main course of methane production in anaerobic reactor. Known dozens of methanogenic bacteria genus，only Methanothrix and Methanosarcina take ethanoic acid as substrate，and Methanothrix is usually brunt. Methanothrix was cultivated as superiority bacteria that take ethanoic acid as carbon source，the influence of temperature and inorganic salt on dynamics was analyzed.Results indicate that when the inorganic salinity is adjusted， the total reaction rate constant of the conventional density nutrient fluid is enhanced eight times， and there is remarkable influence on producing the methane of Methanothrix. Choosed the studied temperature factor to make the reference， when temperature and inorganic salt are changed within the range of project scope， the dynamics constant change scope is 0.01～0.43 and 0.04～0.59 respecively. Inorganic salt and temperature have the same magnitude influence. Otherwise，the methane fermentative process of ethanoic acid substrate is studied by suiting for anaerobic hydrolysis dynamics model. It is indicate that the tentative data tally basically with the phase that produces the methane to enter the logarithm growth.