A filter set of a CT scanning device and control method thereof are disclosed. An example of the CT scanning device comprises a gantry, an X-ray generator, a filter set, a detector, and a drive motor. The filter set comprises a disc, a filter disposed on the disc and having a substantially annular groove structure, and a drive shaft connected to the disc. A body thickness of the annular groove structure varies in a circumferential direction and a radial direction. A shaft axis of the drive shaft is parallel to a radiation direction of X-ray. As the drive shaft is driven by the drive motor, the disc rotates around the shaft axis, such that a region of the filter is aligned with the radiation direction of the X-ray, and a body thickness of the region corresponds to a respective X-ray attenuation for an examination region of a subject.
