An optical coherence tomography device includes: an OCT optical system configured to obtain a OCT signal a front observation optical system configured to obtain a front image of the test substance and a controller is configured to: control the OCT optical system to obtain first temporally different OCT signals with respect to the test substance control the front observation optical system to obtain a first front image of the test substance at the time the first OCT signals are obtained control the front observation optical system to obtain a second front image of the test substance after that determine whether or not the plurality of first OCT signals are good based on a positional deviation between the first and second front images and obtain motion contrast data of the test substance when it is determined that the plurality of first OCT signals are good.
