<;P>;PROBLEM TO BE SOLVED: To provide a cell useful for administration or proliferation of an antitumor virus, and to provide the utilization thereof. <;P>;SOLUTION: A human peritoneal mesothelium cell is used as the cell for holding the virus having the antitumor activity. The human peritoneal mesothelium cell is a carrier cell effective for administering the antitumor virus such as HF10 to the abdominal cavity or the like. <;P>;COPYRIGHT: (C)2009,JPO&INPIT