In order to illuminate the function of plankton and macroalgae on transmission of AVNV, samples of macroalgae and plankton were collected he AVNV carried by plankton and different species of macroalgae was identified by PCR and FQ-PCR technique. The result showed that the AVNV was detected from plankton collected at Shazikou in August and at Sanggouwan in April by FQ-PCR, and the copy number of AVNV was 6.92 per liter of sea water, respectively. Twenty of 36 macroalgae samples collected along the sea areas of Shazikou in 14 months were AVNV positive, accounting for 55.56% of the total number. The positive samples include seven species which are Enteromorpha. prolifera ,Gelidium. crinale, E. linza, Halymenia floresia, Gracilaria textorii and. Five of 24 macroalgae samples collected along the sea area of Sanggouwan in nine months were AVNV positive, accounting for 20.83% of the total number,the positive samples belong to three species including samples collected along sea area of the highest AVNV number being 7.68 /0.1 g in fresh sampleU. pertusa samples collected were AVNV positive, the /0.1g in . The present results implied that plankton and some of macroalgaes could carry AVNV, and the scallops could be infected when they take plankton carrying virus as food. The role of macroalgae carrying AVNV in transmission of AVNV remains to be further studied.