To suppress the coloring of a glass substrate used at an output section and prevent the reduction of the luminance of the output section by using the boro-silicate glass containing cerium oxide for the glass substrate.

This X-ray image tube is constituted of a vacuum envelope 12, an X-ray input section 13 and an output section 36 provided on the vacuum envelope 12, and multiple focusing electrodes 14 and a cylindrical anode 15 provided along the inner wall of the vacuum envelope 12 between the input section 13 and the output section 36. The output section 36 is constituted of a glass substrate 40 made of boro-silicate glass containing cerium oxide of 0.1-5wt.% and having the expansion coefficient of 45×10-7-62×10-7/°C, a phosphor layer 41 provided on the input side, an output screen 22 having a metal back film 42 provided on the phosphor film 41, and metal rings 31, 32 hermetically connecting the peripheral edge of a glass substrate 40 and the vacuum envelope 12.