A position detection device for detecting a position of a rack shaft having a rack teeth portion that meshes with a pinion gear in a part in an axial direction is provided with a coil that is arranged around a periphery of the rack shaft, and a calculation unit that calculates the position of the rack shaft based on an inductance of the coil. The coil is arranged to surround at least a part of the rack teeth portion, and the inductance changes in accordance with the position of the rack shaft.