Acute viral necrosis virus (AVNV) is closely associated with significant mortalities of the Zhikong Scallop, Chlamysfarreri in China.From May 2008 to December 2009, we surveyed the scallop infection with AVNV monthly in two bays under different culture model by loop-mediated isothermal amplification specific to AVNV.AVNV infection rate and mortality of scallop were observed to be very high in summer in the solo-culture area of Liuqinghe Bay.However, the infection rate and mortality of scallop maintained at a low level in summer in the kelp-scallop polyculture area of Sanggou Bay.The survival rate of two kinds of scallop families was about 43% and 90% in Liuqinghe Bay and Sanggou Bay, respectively.Our study showed that kelp-scallop polyculture model could significantly reduce the AVNV infection rate of scallop and improve the survival rate of scallop.Our results indicated that the kelp-scallop polyculture model is an important measure to protect the mollusks from viral attack.