An X-ray imaging apparatus having an improved structure to reduce noise generated when a position of an X-ray generator is fixed in position includes an X-ray generator, an X-ray detector, a moving carriage coupled with one end of the X-ray generator, a guide rail, and a holding unit disposed at an inner side of the moving carriage to hold the position of the X-ray generator, wherein the holding unit includes a contact pad to contact the guide rail to hold the moving carriage, a magnetic body to move the contact pad using magnetic force, and a holding plate coupled to the contact pad to move according to operation of the magnetic body and including a buffer material capable of absorbing noise or vibration.