PROBLEM TO BE SOLVED: To provide an optical tomography device in which quality of tomographic images are improved by suppressing as much as possible a decrease in light volume of measurement light for effectively acquiring a tomographic image, in the optical tomography device that acquires the tomographic image by giving measurement light to an optical probe having a plurality of optical fibers (light guiding means), and to provide an optical tomographic image acquisition method thereof.SOLUTION: An OCT processor that supplies the measurement light to an OCT probe having a plurality of channels of optical fibers includes an optical switch 13 that selectively gives light emitted from an OCT light source 13 to an optical fiber of the OCT probe. By means of a pre-scan, a tomographic image of a whole circumference of the OCT probe is acquired, thereafter based on the tomographic image, optical fibers of channels that can acquire effective tomographic images are determined. The measurement light is supplied only to the determined optical fibers by the optical switch 13. Further a mechanism is provided for adjusting a rotational position of the optical fiber in a sheath of the OCT probe according to a measurement area for acquiring the effective tomographic image.
