To explore the etiology of a serious infectious disease affecting Rana grylio at a farm in Sichuan Province，pathological examinations and pathogen isolation were conducted on the diseased frogs.The isolated pathogen was identified using transmission electron microscopy，PCR detection，and phylogenetic analysis.External clinical signs included limb swelling and ulcerations on the body surface.The dead frog exhibited an enlarged liver，spleen and kidney.Histopathological observations revealed that the liver，spleen，kidney and other organs exhibited damage characterized by significant degeneration and necrosis foci.The carp epithelioma papulosum cyprini （EPC） cell line，inoculated with diseased samples at 25 ℃，demonstrated typical cytopathic effects （CPE） after four days，including rounding and shedding，with a TCID₅₀ of 10^4.12/0.1 mL.Transmission electron microscopic observation showed that the virus exhibited a regular hexagonal shape with a crystalline array of its capsid，and the diagonal diameter measured approximately 165 nm.PCR by using specific primers for the major capsid protein （MCP） gene was performed on the internal tissues of infected frogs and on EPC cells with CPE，yielding positive results.Phylogenetic analysis based on MCP gene sequences indicated that the sequences of isolated virus shared over 99% identity with ranavirus and was classed as FV3-like.This study confirmed that the isolated virus，designated TSL210813，is a ranavirus，responsible for the disease observed in R. grylio.