Provided is an optical tomographic imaging apparatus capable of, when imaging a tomographic image of an object, monitoring an incident state represented by an incident position and an incident angle of a measuring beam group with respect to the object, causing the measuring beam group to form an image at a predetermined position of the object, and obtaining the tomographic image at high speed. The optical tomographic imaging apparatus is featured in that one of multiple beams emitted from a light source to be split and multiple beams emitted from multiple light sources are split into a measuring beam group and a reference beam group, and the optical tomographic imaging apparatus includes a monitoring device for obtaining a monitoring image of the object, thereby capable of monitoring an incident state represented by an incident position and an incident angle of the measuring beam group with respect to the object.
