NOVELTY - Fermenting biomass biogas comprises e.g. preparing material for straw collection, chopping, drying, grinding, mixing, adding corn flour, mixing, adding water, wetting, turning, adding water, composting, degrading, adding straw leavening agent, spraying ammonium bicarbonate solution, straw paving, covering, stack, punching holes, covering straw stacking, feeding in digester, mixing raw materials, adding half ammonium bicarbonate solution, biogas fermenting biologically active additives, other half mixture and water, sealing, and start composting and fermentation.    USE - The method is useful for fermenting biomass biogas (claimed).    ADVANTAGE - The method: uses simple fermentation raw materials; has reduced fermentation initiating time and improve energy efficiency.    DETAILED DESCRIPTION - Fermenting biomass biogas comprises (i) preparing material for straw collection, chopping fresh product, drying, grinding, mixing, adding corn flour, mixing evenly and keeping aside, (ii) taking the pretreated step (i) obtained straw and adding water in mass ratio of 1:1, wetting for 15-24 hours, turning the straw, mixing with water to obtain moisture content of 65-70%, (iii) composting and degrading for tight piling to obtain a thickness of 30cm, adding straw leavening agent to pre-processed straw, spraying ammonium bicarbonate aqueous solution uniformly to obtain primary processed straw, straw paving for primary process has 3-4 layer, covering using plastic film cover, stacking straw piling, punching periphery and top of each stack with 30-50 cm hole, covering the straw stacking with thin film, leaving gap at the bottom, maintaining the stacking temperature above 50 degrees C for generating white mycelium to be used as raw material for fermentation, and (iv) feeding fermentation as pit foot sludge inoculum or foot sludge digester, mixing the step (iii) resulting fermentation raw materials and half ammonium bicarbonate solution into the digester, adding biogas fermenting biologically active additives, adding the other half mixture, adding water, controlling fermentation liquid concentration, sealing the digester, maintaining the temperature at 15-25 degrees C and start composting and fermentation.