NOVELTY - Biological purification of municipal sewage and recycle of resource involve performing aerobic aeration to activated sludge and original sewage; precipitating sludge water mixture; conveying supernatant into sewage processing system to degrade pollutant in sewage; mixing sludge at bottom of precipitating tank and sludge in anaerobic digestion tank for anaerobic fermentation; converting organic matter into methane gas and adding supernatant with magnesium salt to convert supernatant into guanite precipitate; and discharging residual sludge after anaerobic fermentation.    USE - Method for biological purification of municipal sewage and recycle of resource (claimed).    DETAILED DESCRIPTION - Biological purification of municipal sewage and recycle of resource comprise:    (A) discharging residual sludge produced from a sewage processing system into a sludge activating tank for aerobic aeration in a short time;    (B) discharging the activated sludge and the original sewage into a sludge adsorbing tank at volume ratio of 1:1-3 for aerobic aeration;    (C) precipitating sludge water mixture after aerobic aeration; conveying the supernatant after precipitating into the sewage processing system to degrade the pollutant in the sewage, and discharging the sewage after purifying;    (D) conveying the sludge produced by purification into a sludge activating tank for circulation purifying process;    (E) mixing the sludge adsorbed with pollutant at bottom of the precipitating tank and the anaerobic sludge in an anaerobic digestion tank at volume ratio of 1-2:1 for anaerobic fermentation;    (F) converting the organic matter into methane gas after anaerobic fermentation for recycling;    (G) discharging the supernatant into a crystallizing tank, adding magnesium salt, and regulating the pH value with sodium hydroxide to convert the ammonium and phosphate into guanite precipitate for recycling;    (H) conveying the supernatant in the crystallizing tank into the sewage processing system; and    (I) discharging the residual sludge after anaerobic fermentation.