The invention relates to an X-ray tube with a rotatable anode, an X-ray imaging system and a method for adjusting the focal track of an X-ray tube with a rotatable anode. In order to improve the accuracy of X-ray tubes with rotating anodes and the run out characteristics of rotatable anodes, an X-ray tube with an envelope housing a cathode and an anode assembly is provided, wherein the anode assembly comprises a rotatable disk provided with an annular target forming a focal track, which focal track is rotationally symmetric around a symmetry axis, and a rotor stem for supporting the disk, which stem is rotatably supported around a primary axis of rotation. The stem is provided with a mounting surface to support the disk and the disk is provided with an abutment surface to be mounted to the mounting surface. According to the invention, correction means are arranged between the mounting surface and the abutment surface such that a run-out of the focal track in relation to the axis of rotation is adjustable.