When the thickness of the panel at an X axis end of the useful portion is expressed by Tx (mm), the thickness thereof at a Y axis end is expressed by Ty (mm), the thickness thereof at the center is expressed by Tc (mm) and an outer dimension of the panel along the diagonal axis direction is expressed by D (mm), 0.8≦(100×Tc/D)2×(Tx/Ty)≦2.2 and 0.012≦Tc/D≦0.019 are satisfied. Accordingly, the stress generated in a short side and that generated in a long side in a sealing portion in an exhausting process are substantially equalized. As a result, cracking of the panel can be reduced in the exhausting process even when the panel is made thinner. Therefore, it is possible to provide a cathode ray tube that is easy to manufacture and has a lighter and less expensive panel.