Abstract: There is provided an adhesion restraint method of a radionuclide to a carbon steel material of an atomic energy plant, in which an adhesion restraint effect of the radionuclide to the carbon steel material can continue for a longer term. A film forming apparatus is connected to a carbon steel purification system pipe of a BWR plant. A nickel formate aqueous solution and hydrazine are injected into a circulation pipe of the film forming apparatus. An aqueous solution including nickel formate and hydrazine is guided into a purification system pipe subjected to chemical decontamination, and a nickel metal film is formed on an inner surface of the pipe. A platinum ion aqueous solution and hydrazine are injected into the circulation pipe, and an aqueous solution including a platinum ion and hydrazine is supplied to the purification system pipe so as to adhere platinum to the surface of a nickel metal film. The film forming apparatus is detached from the purification system pipe, and the BWR plant is started.