A human poliovirus receptor (PVR) gene was used to generate transgenic mice that express PVR transcripts and poliovirus binding sites in a wide range of tissues. lntracerebral inoculation of PVR transgenic mice with poliovirus type 1, Mahoney strain, resulted in viral replication in the brain and spinal cord and development of paralytic poliomyelitis. PlIMahoney did not replicate or cause paralysis in nontransgenic mice. PVR transgenic mice failed to develop clinical disease when inoculated intracerebrally with the live attenuated Sabin type 1 vaccine strain. These results demonstrate that the PVR is the major determinant of poliovirus host range in mice. Transgenic mice expressing human PVR should be useful for studying poliovirus neurovirulence, attenuation, and tissue tropism, and for development and testing of poliovirus vaccine strains.