Abstract: A strain of duck hepatitis A virus 1 subtype a (DHAV-1a), coded as FJ1605, was isolated from the mule ducklings with pancreatitis. It was identified by RT-PCR analysis and a neutralization test in duck embryos that showed the strain specifically being neutralized by the anti-DHAV-1a hyperimmune serum. Molecular characteristics of VP1 gene of the virus was analyzed to indicate the nucleotide to be 714 bp in length with a homology with those of other DHAV-1a isolates ranging from 98.1% to 99.7% and sharing the greatest similarity to strain FJ1220.On the other hand, the homology between FJ1605 and DHAV-2 was merely 65.7%; and, that between FJ1605 and DHAV-3, approximately 68.3%. Phylogenetic analysis on the VP1 gene also showed FJ1605 to be in the viral lineage of DHAV-1a. Furthermore, an animal infection test clearly displayed the same clinical symptoms as those shown inclinical cases. Thus, it was concluded that the pancreatitis in the mule ducklings was caused by DHAV-1a.