Abstract: DNA vaccines, also known as genetic or nucleic acid vaccines involve the transfection of cells in vivo by introducing DNA plasmid carrying an antigen-coding gene resulting in an immune response. The purpose of this article is to describe DNA vaccination, to discuss its importance, to review different technologies for improving expression of antigens and to illustrate how it could serve as an alternative for conventional vaccines. DNA vaccines have been prepared against bacterial and viral infections, tumors and allergies and were found to be efficacious in animal studies. These offer number of advantages in terms of ease of administration, manipulation, amplitude and duration of immune response, chemical and biological stabilities and simplicity of manufacture with cost consideration. But, this futuristic alternative needs an elaborate research on its efficacy and associated risks in order to establish the clinical utility of DNA vaccines. This article will explore various aspects of DNA vaccines including its associated advantages, disadvantages, mechanism of action, experimental models studied with a brief overview of second generation vaccines.