A new mycovirus was identified in Trichoderma harzianum strain 137 isolated in Xinjiang province, China. The whole genome sequence of the mycovirus was determined by metagenomic sequencing, RT-PCR, and RACE cloning. The mycovirus contained two genomic segments. The first segment was 2088 bp long and contained a single ORF (ORF1) encoding the RNA-dependent RNA polymerase (RdRP) (72.26 kDa). The second segment was 1634 bp long and also contained a single ORF (ORF2) encoding a hypothetical protein of 37.472 kDa. We named this novel mycovirus "Trichoderma harzianum bipartite mycovirus 1" (ThBMV1). Phylogenetic analysis showed that ThBMV1 clusters with other unclassified dsRNA mycoviruses.