NOVELTY - Improving anaerobic digestion gas production performance of corn straw, comprises (i) crushing naturally drying and mildew-free corn straw, pre-processing by adding a pre-processing agent, namely sodium hydroxide, adding water, mixing, and carrying out acidification process using activated sludge; (ii) adding water to reaction vessel, mixing, sealing, and placing in a shaker filled with nitrogen; (iii) adding step (ii) material into a continuous flow stirred-tank reactor (CSTR) reactor as an anaerobic reactor, adding anaerobic sludge and corn straw; and (iv) carrying out methanation process.    USE - The method is useful for improving anaerobic digestion gas production performance of corn straw (claimed).    ADVANTAGE - The method achieves the separation of biological material in acidification stage and methanation stage; enhances the bacterial activity during acidification and methanation phasse; has stable process conditions, and high efficient operation; and improves the biodegradable function of corn straw.    DETAILED DESCRIPTION - Improving anaerobic digestion gas production performance of corn straw, comprises (i) choosing naturally drying and mildew-free corn straw, and crushing into 20 mesh sieve by in a pulverizer, pre-processing by adding a pre-processing agent, namely sodium hydroxide in an amount of 2% to the dry weight of corn straw, adding water in an amount of 6 times the dry weight of corn straw and sodium hydroxide solution, and uniformly mixing by placing at 40 plus minus 2 degrees C environmental conditions, storing by sealing, where the pre-processing is carried out for 1 day, and then carrying out acidification process by using activated sludge obtained from a sewage treatment plant, to obtain pre-processed corn straw, where 52 g corn stalks added is relative to 10-50 g activated sludge; (ii) adding 80% water to the total volume of reaction vessel, uniformly mixing, sealing, placing in a shaker filled with nitrogen, where the constant temperature of the shaker, is 40 plus minus 2 degrees C, and measuring pH by using a pH meter every day, and terminating the acidification process once the pH reaches below 5.5; (iii) adding the step (ii) material into a continuous flow stirred-tank reactor (CSTR) reactor used as an anaerobic reactor, adding 52 g anaerobic sludge into anaerobic reactor, adding pre-processed 12g corn straw, adding 80% water into reaction vessel, filling with nitrogen, and setting the reactor temperature at 35 plus minus 2 degrees C; and (iv) carrying out methanation process by adding the material into the reactor until the pH reaches 7, discharging the acidified raw material, feeding the raw material every day on timely basis, where the material feeding and discharging volume is maintained for 40 days.