Classical swine fever (CSF) is a kind of infectious disease which could induce acute, febrile and fatal disease in swine. This disease displays with wild prevalence and high mortality, and could lead to significant damage for the pig industry all over the world. At present, most CSF epidemic countries or areas still prevent the CSF virus (CSFV) infection mainly by the vaccination of CSFV live-attenuated vaccine (LAV). However, the traditional LAV could not differentiate the CSFV antibody of vaccinated pigs from infected ones, so it is very urgent to develop the new tag vaccines to purge and even eliminate CSF. In recent years, many domestic and international researchers continuously modify the genome of CSFV wild strains or attenuated strains by molecular biology and genetic engineering methods to construct new LAVs allow differentiation between infected and vaccinated animals (DIVA) , and most of which are established based on Erns and E2 genes. Among these DIVA vaccines, some candidate vaccines could produce good immune effects and could be used to diffrentiate naturally infected pigs from vaccinated ones, and they are hopeful to replace the traditional attenuated strain vaccines in the future.