An interdental cleaning tool comprising: a base part including: a shaft part extending in a specific direction and having a shape insertable into an interdental space, the shaft part having an insertion end formed on one end in the specific direction and a base end formed on the other end in the specific direction; and a grip part extending in the specific direction from the base end in a manner to separate from the shaft part and having a shape grippable with fingers, a cleaning part around the shaft part and, wherein the shaft part includes a groove forming part having a first guide groove formed on one side with respect to an axially parallel plane, the axially parallel plane including a center of the shaft part and being parallel to the specific direction, and a second guide groove formed on the other side with respect to the axially parallel plane, and the first guide groove and the second guide groove extend in an axial direction of the shaft part from the insertion end toward the base end and have a shape recessed toward the center of the shaft part from an outer peripheral surface of a region other than the first guide groove and the second guide groove in the shaft part, wherein the cleaning part includes a cleaning body covering an outer peripheral surface of the groove forming part from the insertion end and having a dimension equal to or less than a dimension in the axial direction of the shaft part, and brush bristles each having a shape projecting outward in an axially perpendicular direction perpendicularly intersecting the axial direction of the shaft part from an outer peripheral surface of the cleaning part body, and wherein the cleaning part is formed of a resin material having a hardness lower than a hardness of the shaft part, and wherein a thickness of an overlap part of the cleaning part, the overlap part overlapping the first guide groove and the second guide groove in an axially perpendicular direction perpendicular to an axial direction of the shaft part, is set to be larger than a thickness of a non-overlap part of the cleaning part other than the overlap part, characterized in that each of the brush bristles is formed at a position that overlaps the overlap part in the axially perpendicular direction. a shaft part extending in a specific direction and having a shape insertable into an interdental space, the shaft part having an insertion end formed on one end in the specific direction and a base end formed on the other end in the specific direction; and a grip part extending in the specific direction from the base end in a manner to separate from the shaft part and having a shape grippable with fingers, a cleaning part around the shaft part and, wherein the shaft part includes a groove forming part having a first guide groove formed on one side with respect to an axially parallel plane, the axially parallel plane including a center of the shaft part and being parallel to the specific direction, and a second guide groove formed on the other side with respect to the axially parallel plane, and the first guide groove and the second guide groove extend in an axial direction of the shaft part from the insertion end toward the base end and have a shape recessed toward the center of the shaft part from an outer peripheral surface of a region other than the first guide groove and the second guide groove in the shaft part, wherein the cleaning part includes a cleaning body covering an outer peripheral surface of the groove forming part from the insertion end and having a dimension equal to or less than a dimension in the axial direction of the shaft part, and brush bristles each having a shape projecting outward in an axially perpendicular direction perpendicularly intersecting the axial direction of the shaft part from an outer peripheral surface of the cleaning part body, and wherein the cleaning part is formed of a resin material having a hardness lower than a hardness of the shaft part, and wherein a thickness of an overlap part of the cleaning part, the overlap part overlapping the first guide groove and the second guide groove in an axially perpendicular direction perpendicular to an axial direction of the shaft part, is set to be larger than a thickness of a non-overlap part of the cleaning part other than the overlap part, characterized in that each of the brush bristles is formed at a position that overlaps the overlap part in the axially perpendicular direction.