In vitro-transcribed (IVT) mRNA represents a novel generation of drugs and has attracted much attention. The synthetic mRNA can be engineered to deliver genetic information and express proteins elegantly and transiently. However, there are several inherent challenges of the drug class, such as instability, inefficient in vivo delivery of mRNA and among others. The recent technological advances have provided the basis for a broad range of potential applications. For example, mRNA-based immunotherapy, such as cancer immunotherapy and infectious disease vaccines, have come into the stage of clinical development, and acquired encouraging preliminary results in both animal models and humans. Meanwhile, there are several other emerging novel applications, including protein replacement therapy, regenerative medicine, cell engineering as well as gene editing approach. We present here multiple potential mRNA-based applications.