SummaryAxial transverse tomograms of maxillary cancers are discussed for their significance in the diagnosis. In comparison with other techniques of radiography, axial transverse tomography is especially useful for detecting lesions of the anterior wall and posterior wall of the sinus maxillaris, fossa infratemporalis, processus pterygoideus, sinus ethmoidalis posterior and sinus sphenoidalis. This fact is detailed by the actual cases. It is advocated that maxillary cancers will be classified into 4 types, according to the findings of the axial transverse tomogram. There are a few interrelationships between the classification by conventional tomography and that by the axial transverse tomography. In order to realize the extent of maxillary cancers as accurately as possible, it would be necessary to obtain the findings of both the axial transverse tomograms and the conventional tomograms.