Porcine reproductive and respiratory syndrome (PRRS) is the severest disease of pigs worldwide,caused by a highly genetically diverse RNA virus,called Porcine reproductive and respiratory syndrome virus (PRRSV).The research summarized the genome characteristics of PRRSV particles and the most updated knowledge of structure protein function,and introduced the intellectual of PRRSV transmission and host immune response,which is very important for prevention and control for PRRS.A report showed that mass vaccination can stabilize the immunity of the entire herd,and this is the first required step for a PRRS eradication plan.However,the attenuated live vaccines may not achieve a valid prevention.The final goal of the EU project is to develop new generation,efficacious and safe maker vaccines that can be adapted to temporary changes and geographical differences.Robinson reported that broadly antibodies could neutralize all rapidly evolving type Ⅰ and type Ⅱ viruses,while further studies are expected to elucidate mechanisms of neutralizing antibody production and maturation and to investigate conserved epitope targets of cross-neutralization in this rapidly evolving virus.