To provide a device for measuring the inflow, with which the measurement of the inflow of a workpiece when press forming is performed with high accuracy, at low cost.

In the device 10 for measuring the inflow, with which the inflow of the workpiece 3 when press forming is performed, the device includes: a pedestal part 11; a scriber 13 which is erected on one side of the pedestal part 11 and a convex bead inserting part 17 which is provided on the surface on one side of the pedestal part 11 and which is inserted in the bead-shaped portion 3a formed on the workpiece 3. The bead inserting part 17 is formed from a thermoplastic material which is deformable into an optional shape by being softened when heated to not lower than a first temperature and is hardened when cooled to not higher than a second temperature.