A cutting tool holder that supports a cutting insert including a rake face, a flank face continuous to the rake face, and a cutting edge constituted of a ridgeline that defines a boundary between the rake face and the flank face, the cutting tool holder comprising: a holder body having a seat face on which the cutting insert is placed; a pressing member that positions and fixes, to the holder body, the cutting insert placed on the seat face; and a fixing member that fixes the pressing member to the holder body, wherein the pressing member has a front end portion and a base end portion, the front end portion being an end portion close to the cutting edge of the cutting insert placed on the seat face, the base end portion being an end portion distant away from the cutting edge of the cutting insert placed on the seat face, the front end portion is provided with a first coolant ejection hole via which coolant is ejected, a first flow path through which the coolant flows is provided inside the holder body, characterized in that a coolant reservoir and a second flow path are provided inside the pressing member, the coolant reservoir is connected to the first flow path when the pressing member is fixed to the holder body, the coolant reservoir stores the coolant supplied from the first flow path, and the second flow path supplies, to the first coolant ejection hole, the coolant stored in the coolant reservoir, in a cross section orthogonal to a flow direction of the coolant, the coolant reservoir has a cross sectional area larger than a cross sectional area of each of the first flow path and the second flow path, and the coolant reservoir is disposed at the base end portion side relative to a position at which the pressing member is fixed to the holder body, in a direction from the front end portion toward the base end portion. a holder body having a seat face on which the cutting insert is placed; a pressing member that positions and fixes, to the holder body, the cutting insert placed on the seat face; and a fixing member that fixes the pressing member to the holder body, wherein the pressing member has a front end portion and a base end portion, the front end portion being an end portion close to the cutting edge of the cutting insert placed on the seat face, the base end portion being an end portion distant away from the cutting edge of the cutting insert placed on the seat face, the front end portion is provided with a first coolant ejection hole via which coolant is ejected, a first flow path through which the coolant flows is provided inside the holder body, characterized in that a coolant reservoir and a second flow path are provided inside the pressing member, the coolant reservoir is connected to the first flow path when the pressing member is fixed to the holder body, the coolant reservoir stores the coolant supplied from the first flow path, and the second flow path supplies, to the first coolant ejection hole, the coolant stored in the coolant reservoir, in a cross section orthogonal to a flow direction of the coolant, the coolant reservoir has a cross sectional area larger than a cross sectional area of each of the first flow path and the second flow path, and the coolant reservoir is disposed at the base end portion side relative to a position at which the pressing member is fixed to the holder body, in a direction from the front end portion toward the base end portion.