In a blood pressure information measurement device cuff, a first flexion point and a second flexion point at which a curvature radius changes are provided in a curler, and a straight line-shaped connection portion is provided between the first flexion point and the second flexion point so as to be located inside a curve formed by extending a first curved portion and a second curved portion that are located at the ends of the curler at the first flexion point and the second flexion point, according to the respective curvatures. Through this, it is possible to provide a blood pressure information measurement device cuff, and a blood pressure information measurement device provided with such a cuff, that can reduce error in a blood pressure measurement by reducing errors in changes in the volume of a fluid bladder.