Japanese encephalitis (JE) is a vaccine-preventable acute encephalitis disease that is caused after Japanese encephalitis virus (JEV) through infected Culex tritaeniorhynchus mosquito bite. With the advent of mouse brain-derived inactivated vaccines during the 1950s, the JE vaccines have come a long way with the development of various other licensed and under-development vaccines from Vero cell culture-inactivated vaccines to live attenuated, chimeric recombinant vaccines. This chapter is aimed to review the production process, adjuvants used, immunogenicity, and efficacy of the licensed ongoing vaccines along with research issues associated with the vaccines under development against JEV infection. The chapter also aims to identify some of the disadvantages of ongoing vaccines. Although the phylogenetic sequence analysis of JEV strains has confirmed the presence of a single serotype, the recent mutations leading to the re-emergence of the virus have raised concern over the efficacy of the available vaccines justifying the need for surveillance and newer safe vaccines in the future with better immunogenicity and efficacy.