PURPOSE: To simply and surely remove organic compounds incorporated in gas such as oxygen, hydrogen, nitrogen charged into a bomb before supplying the gas to a fuel cell or the like by allowing a noble metal particle to be carried on a ceramic carrier as a gas cleaning agent capable of regeneration.

CONSTITUTION: Chloroplatinic acid is dissolved in water, in which silica particles are charged and a reducing agent such as sodium borohydride aq. solution is added while stirring, is completely reduced and after washing and drying, the gas cleaning agent capable of regeneration and composed of the silica carrying the noble metal such as platinum is obtained. When the gas from the bomb is passed through the gas cleaning agent packed in a tube and heated, the organic compounds in the gas is adsorbed and removed.