In this application is described a protective DNA vaccines against infection with HFRS- and HPS-associated hantaviruses. The vaccines were constructed by subcloning cDNA representing the medium (M) (encoding the G1 and G2 glycoproteins) into the DNA expression vector pWRG7077. Animals vaccinated with the M construct developed a neutralizing antibody response. Passive transfer experiments show that serum from vaccinated animals, when injected on days 4 or 5 after challenge, protected animals from lethal disease.