The present invention relates to a recombinant vaccinia virus in which the expression of some genes is inhibited, and a use thereof. The recombinant vaccinia virus of the present invention selectively kills cancer cells, and has an excellent reproducibility in cancer cells. Also, the virus has a lower toxicity to normal cells, and thus has an advantage of being safe for a human body. Therefore, the recombinant vaccinia virus of the present invention can be effectively used as a composition for treating cancer.
