An X-ray imaging apparatus and method for controlling the X-ray imaging apparatus are provided. The X-ray imaging apparatus includes an X-ray source configured to generate and emit X-rays onto an object, an X-ray detector configured to detect the X-rays transmitted through the object and convert the X-rays into an electrical signal, a heating portion located at an upper portion of the X-ray detector configured to contact a lower part of the object, a heat transfer portion configured to transfer heat produced in the X-ray source to the heating portion, and a thermal insulation member located between the X-ray detector and the heating portion configured to block heat from being transferred to the X-ray detector.