Interest in the development of vaccines based on nucleic acids appeared thirty years ago, but in the last ten years their application has been intensive for the prevention of infectious diseases and therapy of cancer and genetic disorders. The reason for so much interest in their development is the great potential of these vaccines. In addition to causing a humoral and cellular immune response by activating both T and B lymphocytes, the process of their production is simple and, after application, there is no danger of developing a violent reaction or even disease. The main drawback of these vaccines is insufficient immunogenicity, i.e. stimulation of the immune system, which is due to instability and insufficient delivery of nucleic acids to cells due to a large amount of negative charge. To date, many solutions have been discovered that could solve this problem. By incorporating nucleic acids into systems that are effective in delivering them to cells, the synthesis of antigens increases, and thus the stimulation of the immune system. Special design and modification of nucleic acid molecules, such as codon optimization and base modification in mRNA, and the addition of adjuvants to DNA increase their stability and, also, immunogenicity. Thanks to these methods, a large number of clinical researches are in circulation today, which could very soon lead to the daily use of these vaccines in the prevention and treatment of diseases.