An X-ray imaging apparatus and method is provided. An X-ray imaging apparatus includes an X-ray radiation unit configured to radiate a first X-ray and a second X-ray onto a target along a predetermined path, an X-ray detection unit configured to detect the radiated first X-ray and the second X-ray that have passed through the target, and an image data generation unit configured to generate cross-section data that respectively corresponds to the detected first X-ray and the detected second X-ray and represents a predetermined cross-sectional layer of the target. The first X-ray is radiated at a location on the predetermined path that is different from a location on the predetermined path at which the second X-ray is radiated, the first X-ray including X-ray spectra that are different from X-ray spectra of the second X-ray.