Quorum sensing (QS) is a form of microbial chemical communication that relies on the small signal molecules to regulate specific group behaviors such as biofilm formation in response to population density.As a new biological strengthen paradigm,the concept of bacterial QS was applied to the formation of aerobic granular sludge (AGS) for wastewater treatment first time.In this study,as element of signal molecular,boron was added into sequential sludge blanket reactor (SBR) to stimulate the growth of AGS.Bioassay with Agrobacterium tumefaciens KYC55 and V.harveyi BB170 reporter strains elaborated activity of N-acylhomoserinelactone autoinducers (AHLs) and autoinducer-2 (AI-2) separately.