An X-ray tube includes: an envelope that is a case; a cathode assembly that emits electrons in the envelope; and an anode including a first member of which at least a portion extends to the outside of the envelope, a second member that is provided in a direction perpendicular to a central axis of the first member, comes into contact with the first member, and has a higher X-ray shielding performance than the first member, and a target that receives the electrons emitted from the cathode assembly and generates X-rays.