PROBLEM TO BE SOLVED: To provide an ophthalmological observation device which makes alignment linked with optical path length adjustment of an OCT optical system.SOLUTION: A measurement optical system of an ophthalmological observation device divides light from a light source into signal light and reference light, generates and detects interference light between the signal light and the reference light via an eye to be examined. An image formation unit 220 forms an image on the basis of the detection result of the interference light by the measurement optical system. Drive units 500, 600, 700 move the measurement optical system. An analysis unit obtains the three-dimensional position of the eye to be examined. A control unit 210 changes the optical path length of the signal light and/or reference light on the basis of the movement content when the measurement optical system is moved in the optical axis direction by the drive units. The control unit moves the measurement optical system by controlling the drive units on the basis of the three-dimensional position obtained by the analysis unit and changes the optical path length by an optical distance substantially equal to the movement distance in the optical axis direction.SELECTED DRAWING: Figure 3A
