show Abstracthide AbstractOpisthorchiidae family liver flukes cause hepatobiliary system diseases, known as opisthorchiasis/clonorchiasis. The chronic forms of these diseases greatly increase the risk of carcinogenesis in biliary ducts. Much has been elucidated regarding the developmental biology of the Opisthorchiidae flukes and the molecular mechanism of their pathological effect on host organisms; however, the role of microRNAs (short non-coding RNAs) capable of influencing the pathogenic process and host-parasite interactions have not yet been comprehensively studied. The aim of the present work was to identify the miRNA genes of the liver flukes and provide a basis for further investigation of the roles of these miRNAs in the complex Opisthorchiidae life cycle and in opisthorchiasis/clonorchiasis pathogenesis.