Electroporation is the process commonly referred to the transient increase in the permeability of cell membranes on submission to electric field pulses. Electroporation has become an increasingly extensive method to enhance in vivo DNA delivery for both gene therapy applications as well as for delivery of DNA vaccines, mostly against cancer. In vivo gene electrotransfer is of special interest since it is the most efficient non-viral strategy for gene delivery and it is worthy of low manufacturing costs, ease of realization and favorable safety profile. No adverse findings observed in toxicology and biodistribution/integration studies have been warranted for the evaluation of this approach in humans. Therefore, gene delivery followed by electroporation is currently being investigated in several clinical trials. The positive outcomes of early studies suggest that the efficacy of gene delivery and immunogenicity has greatly improved by electroporation. This review briefly summarizes salient features and recent findings that have contributed to the rapid progress of electroimmunotherapy as well as an overview of advanced clinical studies in oncology. Translation of in vivo DNA electrovaccination for neurodegenerative diseases as well as future expectations are also discussed.