On the earth, the most abundant and diverse life forms are viruses. Both DNA viruses and RNA viruses play important roles in marine ecosystems via regulating biogeochemical cycles. However, the virome of marine RNA viruses has not been explored so far. Here, we established the global virome dataset of deep-sea RNA viruses that were purified from 133 sediment samples collected from typical deep-sea ecosystems (hydrothermal vents, cold seeps, ocean basins and mid-ocean ridges) of the Pacific Ocean, Indian Ocean and Atlantic Ocean. A total of 85,059 viral operational taxonomic units (vOTUs) were identified, of which only 1.72% were hitherto known, indicating that the deep-sea sediment is a repository of novel RNA viruses. The vOTUs were classified into 20 viral families, including prokaryotic (7.09%) and eukaryotic (65.81%) RNA viruses, of which Retroviridae was the most abundant. Furthermore, circular genome analysis revealed 1,463 deep-sea RNA viruses with complete genomes, the majority of which were unclassified. The distribution and differentiation of deep-sea RNA viruses were mainly influenced by the habitat. Taken together, the deep sea is a reservoir of novel RNA viruses, and our study is the first to analyze the composition and diversity of RNA viruses in deep-sea ecosystems.