Abstract: MicroRNAs (miRNAs), a class of short (21-24 nt) non-coding single-stranded RNA molecules, are encoded by endogenous genes found in the 1990s. They play critical roles in gene expression and regulation through translational inhibition or mRNA degradation in eukaryotes. In this article, we briefly summarized miRNA biogenesis and its regulation mechanism, and reviewed the recent progress in identification of insect miRNAs, their target gene predication and function verification, sequence characteristics and evolution, their biological functions on Drosophila and non-drosphilid insects, available network platform and so on, to provide references for further research. Researches on insect miRNAs showed that they are involved in almost every biological process including cell differentiation, cell proliferation, cell apoptosis, embryogenesis, organogenesis, morphogenesis, physiological metabolism, environmental coordination, cognitive behavior and immune defense. So, the indepth study of their biological functions, regulation and application would become the important aspects in the future.

Key words: miRNA, regulation mechanism, insect, sequence characteristics, biological function, network platform