present invention has sufficient sensitivity as a marker for both ct photographing and mri photographing when the material for the above mri marker is filled into a hollow tube formed of a material that may be employed as the above ct marker in this case the material for the mri marker may be contained by the material for the above ct marker or both the materials may be laminated or formed into bar shapes and so forth in the ct photographing described above it is easy to make out the position of a concerned focus but difficult to make out the shape thereof while in mri photographing wherein there is image distortion peculiar to mri it is easy to make out the shape and size of a concerned focus but difficult to make out the position thereof the use of the above described combination marker that responds to both ct photographing and mri photographing enables one to carry out ct photographing with this marker fixed onto a patient and to then carry out mri photographing without replacing the marker with another accordingly it is possible to prevent displacement in both the ct and mri images and to make out the position shape and size of a concerned focus in a more precise manner in recent years the development of open magnetic resonance imaging and the advancement of computer software have enabled the acquisition of images wherein distortion of mri images is revised in creating synthetic images from these mri images and ct images the marker according to the present invention may greatly help to further increase precision and provide more effective medical treatment plans the.