A hair holder including a tubular body which has: a first opening located at one end; and a second opening located at the other end, and which is configured to allow a lock of hair to be inserted from the first opening toward the second opening and to be capable of being rolled up, the tubular body having a longitudinal direction and a width direction that is orthogonal to the longitudinal direction, wherein the tubular body has two sheets (23A, 23B) that form outer surfaces, and at least one of the two sheets is formed of a color-changeable sheet that satisfies conditions and below: an L* value in an L*a*b* color coordinate space is 90 or less, wherein the L* value is a value before the impregnation of the tubular body with a standard hair treatment agent; and a color difference ΔE* ab value in the L*a*b* color coordinate space between before and after impregnation with a standard hair treatment agent is 1.0 or greater, the standard hair treatment agent containing ammonium thioglycolate in an amount of 6 mass%, ammonium hydrogencarbonate in an amount of 2 mass%, and disodium edetate in an amount of 0.5 mass%, the balance being water, and the standard hair treatment agent being adjusted to a pH of 8.4 at 20°C using a 28 mass% aqueous solution of ammonia; wherein the tubular body has a first surface sheet and a second surface sheet as the two sheets, and when the tubular body is rolled up, the first surface sheet is located on the inside of the tubular body and the second surface sheet is located on the outside of the tubular body, and wherein (i) the second surface sheet has a higher porosity of gaps in the sheet than the first surface sheet, in the case that the second surface sheet includes a slit, the gaps in the second surface sheet is gaps of a portion excluding the slit; and/or (ii) the second surface sheet has higher liquid diffusivity than the first surface sheet; wherein at least the second surface sheet is formed of the color-changeable sheet. wherein the tubular body has two sheets (23A, 23B) that form outer surfaces, and at least one of the two sheets is formed of a color-changeable sheet that satisfies conditions and below: an L* value in an L*a*b* color coordinate space is 90 or less, wherein the L* value is a value before the impregnation of the tubular body with a standard hair treatment agent; and a color difference ΔE* ab value in the L*a*b* color coordinate space between before and after impregnation with a standard hair treatment agent is 1.0 or greater, the standard hair treatment agent containing ammonium thioglycolate in an amount of 6 mass%, ammonium hydrogencarbonate in an amount of 2 mass%, and disodium edetate in an amount of 0.5 mass%, the balance being water, and the standard hair treatment agent being adjusted to a pH of 8.4 at 20°C using a 28 mass% aqueous solution of ammonia; an L* value in an L*a*b* color coordinate space is 90 or less, wherein the L* value is a value before the impregnation of the tubular body with a standard hair treatment agent; and a color difference ΔE* ab value in the L*a*b* color coordinate space between before and after impregnation with a standard hair treatment agent is 1.0 or greater, the standard hair treatment agent containing ammonium thioglycolate in an amount of 6 mass%, ammonium hydrogencarbonate in an amount of 2 mass%, and disodium edetate in an amount of 0.5 mass%, the balance being water, and the standard hair treatment agent being adjusted to a pH of 8.4 at 20°C using a 28 mass% aqueous solution of ammonia; wherein the tubular body has a first surface sheet and a second surface sheet as the two sheets, and when the tubular body is rolled up, the first surface sheet is located on the inside of the tubular body and the second surface sheet is located on the outside of the tubular body, and wherein (i) the second surface sheet has a higher porosity of gaps in the sheet than the first surface sheet, in the case that the second surface sheet includes a slit, the gaps in the second surface sheet is gaps of a portion excluding the slit; and/or (ii) the second surface sheet has higher liquid diffusivity than the first surface sheet; (i) the second surface sheet has a higher porosity of gaps in the sheet than the first surface sheet, in the case that the second surface sheet includes a slit, the gaps in the second surface sheet is gaps of a portion excluding the slit; and/or (ii) the second surface sheet has higher liquid diffusivity than the first surface sheet; wherein at least the second surface sheet is formed of the color-changeable sheet.