High concentration brewery wastewater in anaerobic digestion process is easy to lead to acidification and inhibits the conversion of methane.In order to improve the stability and treatment effect of reactor,the paper used the method of sequencing batch test and took synthetic brewery wastewater as the substrate to investigate the effect of different sizes of activated carbon particles on accelerating UASB sludge process and increasing methane production rate.The reactor operated for 95 days in sequencing batch mode.The influent organic loading increased from 2.9 to 12 kg/(m3·d). The change trend of gas output, VFA, TOC and sludge characteristics in reactor was measured.The results showed that the addition of activated carbon can effectively shorten the time of anaerobic sludge granulation,increase the activity of methanogenic bacteria and improve methane output greatly.TOC and VFA of effluent maintain at a lower level.Furthermore,the powdered activated carbon of less size particles has better promotion effect on UASB reactor than that of granular active carbon and can promote the conversion of methane gas.