The present invention provides a recombinant HSV having the ability to specifically kill tumor cells such as human glioma cells in vivo, useful and safe for treating human glioma, etc. and that can easily put to clinical use. A new recombinant HSV, KeM345, is constructed by inserting a &gamma；34.5 gene transcription unit, which is expressed by Musashi1 promoter, into a ribonucleotide reductase gene site of the genome of a herpes simplex virus (HSV) previously attenuated, by means of homologous recombination and obtained as a purified strain. Since KeM345 is a recombinant virus itself, it can not only induce viral proliferation by being transmitted to culture cells but can also induce viral replication equivalent to that of wild-type HSV, showing an excellent cytotoxic effect (cytolytic ability) selectively upon a malignant glioma.
