PROBLEM TO BE SOLVED: To provide an ox tongue processed food eatable in sashimi sensation suggestive of a raw diet.SOLUTION: A lump of an ox tongue is dipped into salt water (step S101), then dipped into dipping water containing koji added thereto (step S102), then aged (step S103), then vacuum-packaged one by one (step S104), and heated at a heating temperature of 50°C-72°C by steam or a hot water bowl (step S105). Hereby, the ox tongue can be eaten deliciously in sashimi sensation without being cooked.SELECTED DRAWING: Figure 1