A method for manufacturing chlorine dioxide gel includes the following steps: a step of dissolving peg-copolymer bis-decyltetradeceth in hot water to form an aqueous solution of peg-copolymer bis-decyltetradeceth a step of heating the aqueous solution of peg-copolymer bis-decyltetradeceth obtained in the above step to form a gel like colloid a step of dissolving pure chlorine dioxide gas in water to form an aqueous solution of chlorine dioxide and a step of uniformly mixing the aqueous solution of chlorine dioxide and the colloid of peg-copolymer bis-decyltetradeceth to form a chlorine dioxide gel, whereby with the above steps, a method for manufacturing chlorine dioxide gel that stably preserves chlorine dioxide gas in a gel is provided.
