Abstract: miRNAs are negative regulators of gene expression in cell. Artificial miRNAs (amiRNA), designed according to the production and principles of natural miRNA, using one or several specific genes as targets, can inhibit gene expression efficiently and specifically. At present, the technology of amiRNA is widely applied in many research fields, such as regulation of gene expression and antivirus． The recent progress in the function priciple of miRNA, the optimization design of amiRNA, gene construction and the application technology was reviewed.

Key words: miRNA, artificial miRNA, design priciple