Abstract: The in vitro transcribed (IVT) mRNA technology has progressed rapidly and the application of mRNA vaccines in the COVID-19 pandemic made it become the most talked-about topic. Compared with protein drugs, IVT mRNA has a lower cost; it can be modular produced and its sequence can be modified easily, so it has a broad application prospect. However, due to its short history, mRNA drugs face the problem of lacking sufficient clinical data, and there is no quality control standard for mRNA drugs except mRNA vaccines. We overview the sequence design, delivery vectors, administration, application prospect and safety considerations of mRNA drugs. We also discussed the quality control of mRNA drugs briefly.