Provided is an optical tomographic imaging apparatus which enables simplification and cost reduction without reducing accuracy when moving part of an object is moved in an optical axis direction of measuring beam. The apparatus using return beam of measuring beam reflected or scattered by an object and reference beam reflected by a reference mirror to image the tomographic image, includes: a reflecting position controlling device for controlling the reflecting position of the reference mirror a detecting device for a position in a moving part having an optical system for observing the moving part illuminated by an optical system imaging the same on an area sensor based on the Scheimpflug principle and detects position information that the moving part is moved in the direction and a device for driving the reflecting position controlling device to control the optical path length of the reference beam based on the position information.