Triploid oysters produce fewer gametes than diploids and develop gonads to variable extents. Reproductive capacity depends on the gene expression of related genes, including gametogenesis and energy metabolism. In addition, microRNAs (miRNAs) play vital roles in the control of gene expression. However, the contributions of miRNAs have not been assessed in the sterile triploid Pacific oysters (Crassostrea gigas). This present work aims to elucidate the role of miRNA-mediated regulation in the gametogenesis of sterile triploid Pacific oysters.