Mucosal immunity is a significant component of the whole immune network of the body, and it is also a unique immune system with unique structure and function, which plays an important role in resisting infection and is the first immune barrier for the body to resist infection. In recent years, more and more studies have reported that microRNAs (miRNAs) is important in the regulation of immune function, and miR-146a is one of the most important miRNAs that coordinates immune response and inflammatory signals, which plays a key role in a variety of biological processes and pathways, including immune response. This paper reviewed the research progress of miR-146a and mucosal immunity.