Osteoclasts,which are derived from monocyte-macrophage precursors,are exclusive bone resorption cells.Limited evidence indicates that a class of small non-coding single-stranded RNAs known as “microRNAs”(miRNAs) is also involved in bone resorption.Although various miRNAs regulate cell proliferation and differentiation,few miRNAs have been reported to play a key role in the regulation of osteoclast differentiation.In this short review,the biology and functional mechanisms of miRNAs in osteoclastogenesis are summarized.The profiling,function,and target prediction of miRNAs are discussed as well.