A medical image obtaining apparatus includes: an image obtainer, which comprises an X-ray emitter configured to emit X-rays toward an object and an X-ray detector configured to detect X-rays that have penetrated the object, and is configured to obtain an image of a portion of the object based on the detected X-rays; a controller configured to generate a virtual ruler which indicates information about a location of the image, based on a rotation angle of the X-ray emitter; and a display configured to display the virtual ruler on the image.