In X-ray imaging, research on material identification using improved detectors and distribution of attenuation coefficients of materials using different energy bands has progressed, and the method for representing information obtained from spectral X-ray CT that are cross-sectional 2D information and 3D rendering of voxel information has been developing. In this research, an attempt was made to represent the inside of an invisible object, which is not normally seen by the human eye, captured by high-definition spectral X-ray CT in a mixed reality, making it possible to observe the object in a form close to reality. As a result, by using a spatial reality display and motion capture, the observer could grasp and rotate the object in the virtual space with their hands to check the internal information from any angle as if it is real object. In addition, by the combination displaying a cross-sectional view using surface rendering and displaying a two-dimensional slice from the DICOM data on the cross-section, the internal structure of the object could be expressed with free angle and without loss of spatial understanding.