Disclosed herein is an X-ray imaging apparatus. The X-ray imaging apparatus includes at least one X-ray emitter which is configured to irradiate an object with X-rays at a plurality of X-ray emission positions, an X-ray detector which is configured to detect X-rays which are emitted by the X-ray emitter and to convert the detected X-rays into an electric signal, and an image processor which is configured to acquire a plurality of original X-ray images which respectively correspond to the X-ray emission positions from the generated electric signal and to estimate a virtual X-ray image which is acquirable at an X-ray emission position located between at least two of the plurality of X-ray emission positions, based on at least two of the original X-ray images.