A display input device comprises a display unit having a flexibility; and a first form change detection unit having a flexibility. The first form change detection unit is able to detect a deformation ascribed to the flexibility as a change in a electrical property. A display input system further comprises a display driving unit that supplies a display signal to the display unit and a signal judging unit that judges a input data based on the change in a electrical property in the first form change detection unit. The input of a first data can be performed by adding the deformation to the display input device.