Abstract: A toilet bowl cleaning tool formed from a single sheet (rectangular and water soluble) for removing a stain from a toilet bowl. The sheet has first fold lines that are fold lines parallel to one of sides of the sheet and that divide the sheet at equal intervals, first fold pieces segmented by the first fold lines, and a second fold line used as a reference for folding the sheet into an approximately L-shape in a cross-section of the tool. After the sheet is folded based on the plurality of the first fold lines so that the first fold pieces are stacked to form an approximately rectangular shape whose longer sides are parallel to the first fold lines, the second fold line is provided to be parallel to the longer sides of the rectangular shape and to divide the shorter sides into an approximately half.