The invention discloses a chemical treatment method for removing corrosive sulfides in insulating oil. The method comprises the steps as follows: 1) sodium hydroxide solid particles and polyethylene glycol are mixed, and oil bath is performed at the constant temperature of 120 DEG C until gelatinoid with a solvent turning dark brown is obtained; 2) the gelatinoid obtained in the step 1) is added to insulating oil containing dibenzyl disulfide and fully mixed, the mixture is subjected to a constant-temperature oil bath reaction at 90-120 DEG C for 2 h for removal of dibenzyl disulfide; 3) the mixed solution obtained in the step 2) is left to stand for layering, a lower gelatinoid layer is removed, and upper insulating oil is reserved. Corrosive sulfides in the oil can be removed quickly and effectively with the chemical treatment method.