To provide an aqueous disinfectant composition which can simply be prepared in a home, a facility, or the like, has a high disinfectant effect, and can supply a foamy iodine-containing disinfectant solution to uniformly and widely disinfect, when used.

Provided is the aqueous disinfectant composition characterized by charging into a refillable foamer container a disinfectant composition containing, as essential components, (a) an iodine-releasing material prepared by the adsorption of 40 to 400 wt% of solid iodine to a polyvinyl acetal-based porous material which has an acetalization degree of 50 to 90 mol% and is obtained by heating at 30 to 100C in a closed container, (b) a surfactant for forming a stable complex with the iodine released from the iodine-releasing material, and (c) water.