DNA vaccines have shown promise as a safe and effective platform for inducing immune responses. Since their discovery over 15 years ago, significant progress has been made in understanding their biology and application. Four DNA vaccine products have been approved for veterinary use, indicating a productive future for this technology. DNA vaccines are non-live, non-replicating, and non-spreading, making them safer than live vaccines. They can induce both humoral and cellular immunity, including killer cytotoxic T lymphocytes (CTLs), which are crucial for fighting infections. DNA vaccines have been tested against various pathogens and tumour antigens, and recent clinical trials have shown their safety and effectiveness in humans. However, their immunogenicity in larger animals and humans is still being optimized. Several strategies are being explored to improve DNA vaccine efficacy, including gene optimization, improved RNA structural design, novel formulations, and more effective delivery methods. The use of DNA vaccines in veterinary medicine has led to renewed interest in this platform. DNA vaccines have the potential to be used for a wide range of applications, including prophylactic vaccines, cancer immunotherapy, and treatment of infectious diseases. Despite their promise, challenges remain in improving their immunogenicity and translating their success from animal models to humans. The future of DNA vaccines depends on continued research and development to optimize their delivery and immunogenicity.DNA vaccines have shown promise as a safe and effective platform for inducing immune responses. Since their discovery over 15 years ago, significant progress has been made in understanding their biology and application. Four DNA vaccine products have been approved for veterinary use, indicating a productive future for this technology. DNA vaccines are non-live, non-replicating, and non-spreading, making them safer than live vaccines. They can induce both humoral and cellular immunity, including killer cytotoxic T lymphocytes (CTLs), which are crucial for fighting infections. DNA vaccines have been tested against various pathogens and tumour antigens, and recent clinical trials have shown their safety and effectiveness in humans. However, their immunogenicity in larger animals and humans is still being optimized. Several strategies are being explored to improve DNA vaccine efficacy, including gene optimization, improved RNA structural design, novel formulations, and more effective delivery methods. The use of DNA vaccines in veterinary medicine has led to renewed interest in this platform. DNA vaccines have the potential to be used for a wide range of applications, including prophylactic vaccines, cancer immunotherapy, and treatment of infectious diseases. Despite their promise, challenges remain in improving their immunogenicity and translating their success from animal models to humans. The future of DNA vaccines depends on continued research and development to optimize their delivery and immunogenicity.