An inclination derivation device of a pointer of a pen shape, is discussed with the pointer including a first electrode installed at an end of an axis and a second electrode installed around the axis. The inclination derivation device includes a sensor of a plane shape that detects a position of the first electrode and a position of the second electrode, and a control portion. The control portion includes a look-up table (LUT) in which a corresponding relation of a value based on a difference between the position of the first electrode and the position of the second electrode, and a compensation value that becomes a base of an inclination of the axis of the pointer is registered; an input value calculation portion that calculates and inputs the value based on the difference to the LUT; and an inclination derivation portion that derives the inclination from the compensation value output from the LUT.