To prevent environmental pollution by refuse, easily provide a cup holder as an attachment to a cup, and provide the cup holder to be applicable to cups of different sizes and flange forms.

Holding members 3 are formed continuously at both ends of a length direction of a sheet member 1 made of thick paper in a rectangular arc form through outward folding lines 2. Cut grooves 4 are formed in the folding line, one on the upper side, and the other on the lower side, to compose a developed structure of a holder. The sheet member 1 is rounded in a length direction against its rigidity while it is twisted in a width direction to engage the cut grooves with each other along the whole length from their upper and lower groove ends 4a, so a down-tapered cylinder part 5 is formed, with the holding members 3 being combined with each other. Into the cylinder part 5, a down-tapered cup 6 having a smaller lower diameter and a larger upper diameter than its upper inner diameter is inserted, and a down-tapered outer circumferential surface of the cup 6 is received by a down-tapered inner circumferential surface of the cylinder part 5 to hold the cup by the holding members 3.