A filovirus, Dehong virus (DEHV), was isolated from Rousettus leschenaultii bats in Yunnan, China, following long-term surveillance. DEHV has a typical filovirus-like morphology, wide cell tropism, and uses Niemann-Pick C1 (NPC1) for entry. It is the largest known filovirus genome, with phylogenetic analysis placing it between Dianlovirus and Orthomarburgvirus, suggesting it belongs to a new genus within the Filoviridae family. DEHV was repeatedly detected in orchards near human settlements, but no associated diseases have been reported. The virus is likely nonlethal to humans, similar to Reston virus. The study highlights the need for further research on DEHV's pathogenicity and potential risks. The region of southern Yunnan and bordering areas is identified as a natural circulation sphere for bat filoviruses. The study also reveals that R. leschenaultii bats are a major reservoir for multiple filoviruses, including DEHV, FiV DH04, and MLAV. The findings emphasize the importance of understanding the ecology and transmission dynamics of filoviruses in this region. DEHV's wide distribution and long-term circulation suggest a broader circulation sphere in southern Yunnan and neighboring Southeast Asia. The study also demonstrates that DEHV can be inhibited by remdesivir, a drug effective against filovirus polymerases. The research underscores the need for continued surveillance and research to better understand the risks associated with filoviruses in this region.A filovirus, Dehong virus (DEHV), was isolated from Rousettus leschenaultii bats in Yunnan, China, following long-term surveillance. DEHV has a typical filovirus-like morphology, wide cell tropism, and uses Niemann-Pick C1 (NPC1) for entry. It is the largest known filovirus genome, with phylogenetic analysis placing it between Dianlovirus and Orthomarburgvirus, suggesting it belongs to a new genus within the Filoviridae family. DEHV was repeatedly detected in orchards near human settlements, but no associated diseases have been reported. The virus is likely nonlethal to humans, similar to Reston virus. The study highlights the need for further research on DEHV's pathogenicity and potential risks. The region of southern Yunnan and bordering areas is identified as a natural circulation sphere for bat filoviruses. The study also reveals that R. leschenaultii bats are a major reservoir for multiple filoviruses, including DEHV, FiV DH04, and MLAV. The findings emphasize the importance of understanding the ecology and transmission dynamics of filoviruses in this region. DEHV's wide distribution and long-term circulation suggest a broader circulation sphere in southern Yunnan and neighboring Southeast Asia. The study also demonstrates that DEHV can be inhibited by remdesivir, a drug effective against filovirus polymerases. The research underscores the need for continued surveillance and research to better understand the risks associated with filoviruses in this region.