A virus named FYL140220 was isolated from naturally infected Triplophysa siluroides in Leshan, Sichuan Province using epithelima popuasum cuprini (EPC) cells. The infected EPC cells showed circular shrinkage, necrosis, and desquamation, which formed significant plaque-lesion characteristics. Diseased tissue suspension filtered from bac- teria and EPC-grown virus were used to inoculate healthy Triplophysa siluroides. As a result, the infected T. siluroides developed similar clinical symptom to those described above and suffered 30% and 40% mortality, whereas the uninfected control EPC cells remained normal. Electron microscopy revealed icosahedral viral particles in the cells. The FYL140220 virus had an average diameter of (103 ± 7) nm, and the hexagonal shape was highly similar to that of other Iridoviridae viruses. DNA was extracted from the EPC-grown virus and naturally and artificially infected internal T. siluroides tissues for polymerase chain reaction (PCR) amplification of the conserved region of the ranavirus major capsid protein (MCP) gene, revealing a 500-bp fragment. The MCP homology and genetic evolution analysis showed that FYL140220 and other ranavirus strains formed a tight cluster and shared 99.8% identity with CGSV-G and 99.6% with RGV. Taken together, these results confirm that FYL140220 is a ranavirus. This is the first report on a natural ranavirus infection and mortality caused by this pathogen in cultured Triplophysa.