Focus adjustment is enabled with respect to an object to be inspected even when an optical member for changing a field angle is inserted in order to change the field angle of an acquiring area of a tomographic image, and a clear tomographic image with a focus on the object to be inspected is acquired. In an optical tomographic imaging apparatus, an optical system includes a focus lens configured to focus a measuring light on the object to be inspected. The optical tomographic imaging apparatus includes a unit configured to compensate, when an optical member for changing a field angle is inserted between a scanning unit and the object to be inspected in order to change the field angle of an acquiring area of a tomographic image, a change in a focus position of the focus lens in association with the inserting.