Disclosed herein is a combined panoramic, CT (Computed Tomography) and cephalometric photographing apparatus including: a base; a supporting pole; an elevation member; a panoramic and CT photographing part; and a cephalometric photographing part. The panoramic and CT photographing part includes: a rotary arm supporting member; a rotary arm arranging an X-ray source part and an X-ray sensor part in such a way that the X-ray source part and the X-ray sensor part are opposed to each other, the X-ray sensor part having a panoramic sensor and/or a CT sensor; and rotary arm driving means. A distance between the X-ray source part and the X-ray sensor part arranged opposed to each other with respect to the rotary arm is variable. The apparatus can conduct all of panoramic photographing, CT photographing and cephalometric photographing, and provide the optimum enlargement ratio according to whether the panoramic photographing or the CT photographing is conducted.