The utility model discloses a titanium window structure X -ray tube, including shell, positive pole subassembly and cathode assembly, the positive pole subassembly is still including anode cap and plate target subassembly, the plate target subassembly with the anode cap welding, the positive pole subassembly is still including the titanium window, the titanium window encircle and weld in the exit window department of anode cap. The utility model discloses an adopt the titanium area as the exit window of X -ray tube, can realize with intrinsically filtration of certain thickness beryllium window equivalence, and the titanium area has good ductility and a welding performance, can with big exit window anode cap realization zonulae occludens, can realize the big radiancy angle outputs of X ray, satisfy X ray inspection equipment to the big radiancy angle demand of ray.