NOVELTY - An anaerobic digestion processing system for kitchen waste comprises a first bioreactor in start period, second bioreactor in active period and a third bioreactor in rotten period; a first digestive juice tank; a second digestive juice tank; a third digestive juice tank; a first pump; a second pump; and a third pump.    USE - The anaerobic digestion processing system or method is useful for kitchen waste (claimed).    ADVANTAGE - The invention can solve the technical problems of long period, low gas output, high salt, volatile fatty acids (VFA) accumulation, and inhibition of ammonia-nitrogen accumulation on gas output when anaerobically digesting the normal kitchen waste.    DETAILED DESCRIPTION - An anaerobic digestion processing system for kitchen waste comprises a first bioreactor in start period, second bioreactor in active period and a third bioreactor in rotten period; a first digestive juice tank; a second digestive juice tank; a third digestive juice tank; a first pump; a second pump; and a third pump; the multiple liquid connecting pipes are connected with each bioreactor and the digestive juice tank; the kitchen waste anaerobic digestion processing system further comprises a gas collecting device for collecting gas; the upper end of each bioreactor is arranged with a first inlet/outlet for back flowing digestive juice and a second inlet/outlet connected with the gas collecting device; the bottom part of each bioreactor is arranged with a digestive juice outlet; the upper end and the lower end of each digestive juice tank are respectively arranged with a digestive juice inlet/outlet and a liquid inlet for adding water adjusting substance; the digestive juice outlet at the bottom of the first bioreactor in start period is connected with the digestive juice inlet/outlet in the upper end of the first digestive juice tank to collect the digestive juice in storing start period; the digestive juice outlet at the bottom of the second bioreactor in active period is connected with the inlet/outlet of the digestive juice in the upper end of the second digestive juice tank; the digestive juice in the second digestive juice tank is delivered into the second bioreactor in activating period by a second pump to self flow the digestive juice in active period; the digestive juice outlet at the bottom of the third bioreactor is connected with the digestive juice inlet/outlet in the upper end of the third digestive juice tank to collect and store the digestive juice in start period by the rubbish layer; and the digestive juice in the third digestive juice tank back flows to the first bioreactor in start period to flow the digestive juice in circulated and crossed manner. An INDEPENDENT CLAIM is an anaerobic digestion processing method for kitchen waste, comprising filling the preprocessed kitchen waste into the first bioreactor, making the first bioreactor enter into start period for anaerobically digesting, after set time, filling the preprocessed new kitchen waste in the third bioreactor, making the third bioreactor enter into the start period of anaerobic digestion; when the first bioreactor, the second bioreactor or the third bioreactor enters into the active period of anaerobic digesting, collecting the digestive juice generated by the bioreactor in active period into the digestive juice tank connected with the bioreactor by the digestive juice outlet at the bottom, preprocessing, back flowing to the digestive juice inlet/outlet in the top of the bioreactor by a pump after preprocessing; when the first bioreactor, the second bioreactor or the third bioreactor enters into rotten period of anaerobic digestion, collecting the digestive juice generated by the bioreactor in rotten period into the digestive juice tank connected with the bioreactor by the digestive juice outlet at the bottom, preprocessing, back filling into the digestive juice outlet in the top of the bioreactor in start period to inoculate bacteria, after adjusting the digestive juice outlet at the bottom of the bioreactor in start period by the digestive juice tank connected with the bioreactor, back flowing to the bioreactor in rotten period.