The invention provides an optical image-measuring device that avoids long examination time and reduces some troublesome tasks. A fundus observation device 1 (optical image-measuring device) splits light that is output from a low-coherence light source 160 into a signal light LS directed toward the fundus oculi Ef and a reference light LR directed toward a reference mirror 174, and detects interference light LC that is generated by superimposing the signal light LS passing through the fundus oculi Ef and the reference light LR passing through the reference mirror 174 using a spectrometer 180 to form tomographic images of the fundus oculi Ef. Furthermore, the device comprises a reference mirror drive mechanism 243 shifting the reference mirror 174 toward the optical path direction of the reference light LR and a information storage part 225 storing the reference mirror 174 position information based on previous tomographic images. The controlling part 210 controls the reference mirror drive mechanism 243 so that the reference mirror 174 shifts into a position based on reference mirror position information related to the eye to be examined E that is stored in the information storage part 225.