To provide the guide light irradiation function of an optical interference measuring device at low cost without incurring an increase in device size.SOLUTION: The optical interference measuring device comprises: a first light source for outputting measurement light having an infrared region wavelength; a second light source for outputting guide light having a visible region wavelength; a fiber coupler including at least a first port to which the measurement light is inputted, a second port to which the guide light is inputted, and a third port from which combined light of the measurement light and guide light is outputted; a measurement unit for irradiating a measurement object with the combined light and receiving return light having been reflected by the measurement object; and a processing unit for acquiring information regarding the distance, speed or vibration of the measurement object on the basis of an interference signal of the return light with reference light. The fiber coupler is composed of single mode fibers the cutoff wavelength of which is shorter than the wavelength of the measurement light and longer than the wavelength of the guide light.SELECTED DRAWING: Figure 1