A method for operating an optical tomographic image photographing apparatus for photographing a tomographic image of an object, the optical tomographic image photographing apparatus comprising an interference optical system including a measurement light source and a splitter; an optical scanner that is arranged in a measurement optical path; a driving part; an image obtaining part that is connected to a detector; a monitor and a control unit; the method comprising: splitting, by the splitter, light emitted from the measurement light source, such that the light is split in the measurement optical path for guiding part of the light to the object as measurement light and in a reference optical path for generating reference light, combining, by the interference optical system, reflected light from the measurement optical path, the reflected light being obtained by reflection of the measurement light on the object, with the reference light from the reference optical path, to guide combined light to the detector; scanning, by the optical scanner, the measurement light on the object; moving, by the driving part, an optical member arranged in the measurement optical path or the reference optical path in an optical-axis direction in order to adjust an optical path difference between the measurement optical path and the reference optical path; obtaining, by the image obtaining part, a tomographic image of the object based on a light receiving signal output from the detector; detecting, by the control unit, positional deviation of the tomographic image in a depth direction thereof based on the signal output from the detector; and correcting, by the control unit, a display position of the tomographic image such that the tomographic image obtained by the image obtaining part is displayed in a predetermined position on the monitor by controlling a display of the monitor based on the detected positional deviation; characterized in that the tomographic image is a B-scan image; the positional deviation is defined by a deviation amount between a peak position and a reference position of the tomographic image based on a luminance distribution on scanning lines extending in a depth direction on the tomographic image; and the method comprises correcting the display position of the tomographic image by moving, by the control unit, the tomographic image in the direction of the reference position by the detected deviation amount (ΔD) to match the reference position and the peak position to each other, and displaying the tomographic image after image processing in a display region of the monitor. splitting, by the splitter, light emitted from the measurement light source, such that the light is split in the measurement optical path for guiding part of the light to the object as measurement light and in a reference optical path for generating reference light, combining, by the interference optical system, reflected light from the measurement optical path, the reflected light being obtained by reflection of the measurement light on the object, with the reference light from the reference optical path, to guide combined light to the detector; scanning, by the optical scanner, the measurement light on the object; moving, by the driving part, an optical member arranged in the measurement optical path or the reference optical path in an optical-axis direction in order to adjust an optical path difference between the measurement optical path and the reference optical path; obtaining, by the image obtaining part, a tomographic image of the object based on a light receiving signal output from the detector; detecting, by the control unit, positional deviation of the tomographic image in a depth direction thereof based on the signal output from the detector; and correcting, by the control unit, a display position of the tomographic image such that the tomographic image obtained by the image obtaining part is displayed in a predetermined position on the monitor by controlling a display of the monitor based on the detected positional deviation; characterized in that the tomographic image is a B-scan image; the positional deviation is defined by a deviation amount between a peak position and a reference position of the tomographic image based on a luminance distribution on scanning lines extending in a depth direction on the tomographic image; and the method comprises correcting the display position of the tomographic image by moving, by the control unit, the tomographic image in the direction of the reference position by the detected deviation amount (ΔD) to match the reference position and the peak position to each other, and displaying the tomographic image after image processing in a display region of the monitor.