The subject of the present invention is to provide a method for producing a silica gel supporting a derivatizing agent for a carbonyl compound that hardly collects carbonyl compounds during production thereof, and a silica gel supporting a derivatizing agent for a carbonyl compound produced by said production method, in order to lower a blank value in measurement of carbonyl compounds. The present invention also relates to a method for producing a silica gel supporting a derivatizing agent for a carbonyl compound characterized by bringing an acid-supported silica gel into contact with an organic solvent containing the derivatizing agent for a carbonyl compound, a silica gel filler supporting a derivatizing agent for a carbonyl compound comprising the silica gel supporting the derivatizing agent for a carbonyl compound produced by the above production method, a method for producing a silica gel supporting a derivatizing agent for a carbonyl compound characterized by treating in advance a silica gel having a cation-exchange group with the derivatizing agent for a carbonyl compound and then bringing it into contact with an organic solvent containing the derivatizing agent for a carbonyl compound, and the like.