We performed metagenomic analyses for RNA viral community by targeting long dsRNA in cellular organisms, a hallmark of infection or replication of both dsRNA and ssRNA viruses except for retroviruses. Sponges on tidal rocks in Tokyo Bay (35.3405 N, 139.6396 E) were sampled at April 2014 and 2015. Purified dsRNAs from the samples were specifically converted into dsDNA, and resultant dsDNAs were sequenced by the Illumina MiSeq platform.