In the title hemihydrate, 2C13H10INO3S·H2O, there are two organic molecules (A and B) and one water molecule in the asymmetric unit. The benzene rings are inclined to one another by 77.98 (1)° in A and 79.81 (9)° in B. The A and B molecules are connected through a water molecule via N—H...O and O—H...O hydrogen bonds. In the extended structure, the A molecules are interlinked via two water molecules through O—H...O hydrogen bonds to generate R44(12) loops. Further, the A and B molecules are linked by N—H...O hydrogen bonds, and thus an [010] chain is formed. Several C—H...O interactions extend the chains into sheet lying parallel to the ab-plane. The sheets are further extended into a three dimensional architecture via a C—H...π interaction.