PURPOSE: To produce fish products for preservation having such a soft bone as to be entirely edible, from which a fishy smell is removed by pretreating fishes, immersing, heating, sealing and pressurizing.

CONSTITUTION: Internal organs, etc., of fishes such as sardine, herring, mackerel pike, etc., are removed, the fishes are washed, dehydrated and immersed in a given solution such as a solution consisting essentially of BENIKOJI (KOJI belonging to the genus Monascus) or in salt water having a given concentration for a fixed time. Then the immersed fishes are preheated, dried, directly roasted with far infrared rays having 2-300μ, preferably 5-30μ wavelength and then cooled until fish body becomes ≤5°C. Then heat-treated fishes are sealed in a proper case, pressurized at given temperature for given time and cooled.