Compared with traditional vaccines,mRNA vaccines have the advantages of easy compilation,high immunogenicity,strong safety and low production cost.The efficient delivery of mRNA to cells and successful expression is the key link for mRNA vaccines to play a role,and also the main bottleneck and pain point of mRNA vaccine research and development.Therefore,screening for cost-effective nucleic acid delivery systems is crucial for mRNA vaccine development.At present,nucleic acid delivery systems with more attention mainly include physical delivery,lipid nanoparticle delivery,polymer delivery,exosome delivery and cationic emulsion delivery.Physical delivery is basically the physical process of getting naked mRNA directly across the cell membrane into the cell.Lipid nanoparticle,polymers,exosomes and cationic emulsions protect mRNA by using themselves as delivery carriers,thereby improving delivery efficiency and reducing immune response.Based on the latest research progress of mRNA vaccines,the author summarized the application prospects and limitations of different delivery methods,and prospected their research prospects.It is expected to provide a theoretical basis for the development of a new delivery system,promote the clinical application of mRNA therapy,and provide a new mRNA vaccine solution for the prevention and treatment of more diseases.