An optical coherence tomography device provided with: an OCT optical system configured to output OCT signal; and an analysis processing unit configured to process the OCT signal and generate motion contrast data of the specimen. The analysis processing unit is provided with: a first image data generation unit configured to process multiple OCT signals to generate first image data representing phase difference information of the multiple OCT signals, and a second image data generation unit configured to process the OCT signal to generate second image data representing amplitude information of the OCT signal. The analysis processing unit generates the motion contrast data based on the phase difference information in the first image data and the amplitude information in the second image data.