A medical tube clamp which presses and occludes a flexible medical tube, the medical tube clamp comprising: a first plate on which a first protrusion is formed; a second plate placed opposing the first plate, and on which a second protrusion which presses the medical tube along with the first protrusion is formed; a connecting portion that connects one end of the first plate in a length direction and one end of the second plate in a length direction, and that is elastically deformable so as to allow the first plate and the second plate to be closer to each other; and a locking unit that is formed extending from the first plate toward the second plate, that locks an other end of the second plate in the length direction, and that maintains an occluded state of the medical tube, wherein a pair of sidewalls which extend in a standing manner are formed on both ends in a width direction on the first plate, a biting-prevention piece is formed extending from the other end of the second plate in the length direction to the second protrusion along the length direction on a center in a width direction of the second plate, the biting-prevention piece protruding toward the first plate, a sloped surface is formed on the second plate, the sloped surface being inclined toward the first plate from both ends in the width direction toward the center in the width direction of the second plate, and an inclination angle θ of the sloped surface with respect to the width direction of the second plate is 10° ~ 60°, and characterized in that the sloped surface protrudes beyond the biting-prevention piece toward the first plate at the center in the width direction of the second plate. a first plate on which a first protrusion is formed; a second plate placed opposing the first plate, and on which a second protrusion which presses the medical tube along with the first protrusion is formed; a connecting portion that connects one end of the first plate in a length direction and one end of the second plate in a length direction, and that is elastically deformable so as to allow the first plate and the second plate to be closer to each other; and a locking unit that is formed extending from the first plate toward the second plate, that locks an other end of the second plate in the length direction, and that maintains an occluded state of the medical tube, wherein a pair of sidewalls which extend in a standing manner are formed on both ends in a width direction on the first plate, a biting-prevention piece is formed extending from the other end of the second plate in the length direction to the second protrusion along the length direction on a center in a width direction of the second plate, the biting-prevention piece protruding toward the first plate, a sloped surface is formed on the second plate, the sloped surface being inclined toward the first plate from both ends in the width direction toward the center in the width direction of the second plate, and an inclination angle θ of the sloped surface with respect to the width direction of the second plate is 10° ~ 60°, and characterized in that the sloped surface protrudes beyond the biting-prevention piece toward the first plate at the center in the width direction of the second plate.