NOVELTY - Improving dry fermentation stability of sludge by adding kitchen waste, comprises e.g. crushing kitchen waste, controlling moisture, mixing with dehydrated sludge, then performing anaerobic fermentation, the fermentation process enters a methanol-producing fermentation stage when content of methanol in the fermentation tank rises to 35%, again adding the kitchen waste and fermenting, when the content of methanol reduces to 35%, using one part of the sludge waste as an inoculation material for next batch of fermentation, and performing aerobic composting stabilization on the remaining material.    USE - The method is useful for municipal sludge treatment and recovering energy from municipal sludge.    ADVANTAGE - The method: solves the problems of low hydrolysis-acidification degree, lack of methane producing substrate, high pH value, ammonium salt accumulation and inhibition of gas production caused by large viscosity of the sludge, high total solid concentration and low carbon/nitrogen value in the dehydrated sludge; and saves equipment investment and land usage when compare to wet fermentation.    DETAILED DESCRIPTION - Improving dry fermentation stability of sludge by adding kitchen waste, comprises (i) crushing kitchen waste until average particle size reaches less than or equal to to 5 mm, controlling moisture so that the moisture content of it is less than or equal to 85%, mixing dehydrated sludge with a moisture content of less than or equal to 80% with the kitchen waste at a weight ratio of 10:1-15:1 so that the moisture content of the mixed material is 75-83% and the pH value is 6.0-7.5, then placing it in an anaerobic fermentation tank to ferment, (ii) starting the fermentation process to increase the gas yield, keeping temperature and stirring conditions, monitoring the pH value and gas producing ingredients of the fermented material on time, when pH value rises to 7.5 or more and the content of methanol in gas production rises to 35%, indicating that the fermentation process enters a methanol-producing fermentation stage, (iii) crushing the kitchen waste until the average particle size reaches less than or equal to to 2 mm, controlling moisture so that the moisture content is 70-80%, adding the crushed kitchen waste to the fermentation tank in the methanol producing stage in batches, where the additive amount of each time is 5-10% of the weight of the dehydrated sludge at the start of fermentation to ensure that the pH value is greater than or equal to 6.6 after adding the kitchen waste, adding the kitchen waste every 5-15 days until the pH value of the fermented material reaches to 7.5 or more, where the kitchen waste needs to be added for one to three times in the methanol producing stage totally, and (iv) when the content of methanol in the gas production reduces to 35% or the gas production rate decreased, using one part of sludge waste of the methanol producing stage as an inoculation material for the next batch of fermentation, and performing aerobic composting stabilization on the rest material, where the stabilized material is used for sludge compositing step of organic fertilizer processing.