A panoramic X-ray photographing apparatus (100; 200) comprising: - a rotary arm (130; 230) for arranging an X-ray light source part (110; 210) and an X-ray sensor part (120; 220) thereon in such a way as to be opposed to each other; and - a rotary arm supporting member (140; 240) for supporting the rotary arm (130; 230), wherein the rotary arm supporting member includes a rotary driving means for rotary driving the rotary arm, a means for driving the rotary arm to a length direction of the rotary arm supporting member, and a means for driving the rotary arm in a direction perpendicular to the length direction of the rotary arm supporting member, or wherein the rotary arm supporting member for supporting the rotary arm has a fixing rotary axis at one end thereof and is rotated in a center of the fixing rotary axis, and wherein the rotary arm supporting member includes a rotary driving means for rotary driving the rotary arm, and a means for driving the rotary arm to a length direction of the rotary arm supporting member characterized in that the X-ray light source part (110; 210) is configured so as to be turned off not to generate X-ray while a line connecting the X-ray light source part and the X-ray sensor part (120; 220) is in contact with a neck cervical vertebrae part of a patient during panoramic photographing. - a rotary arm (130; 230) for arranging an X-ray light source part (110; 210) and an X-ray sensor part (120; 220) thereon in such a way as to be opposed to each other; and - a rotary arm supporting member (140; 240) for supporting the rotary arm (130; 230), wherein the rotary arm supporting member includes a rotary driving means for rotary driving the rotary arm, a means for driving the rotary arm to a length direction of the rotary arm supporting member, and a means for driving the rotary arm in a direction perpendicular to the length direction of the rotary arm supporting member, or wherein the rotary arm supporting member for supporting the rotary arm has a fixing rotary axis at one end thereof and is rotated in a center of the fixing rotary axis, and wherein the rotary arm supporting member includes a rotary driving means for rotary driving the rotary arm, and a means for driving the rotary arm to a length direction of the rotary arm supporting member characterized in that the X-ray light source part (110; 210) is configured so as to be turned off not to generate X-ray while a line connecting the X-ray light source part and the X-ray sensor part (120; 220) is in contact with a neck cervical vertebrae part of a patient during panoramic photographing. wherein the rotary arm supporting member includes a rotary driving means for rotary driving the rotary arm, a means for driving the rotary arm to a length direction of the rotary arm supporting member, and a means for driving the rotary arm in a direction perpendicular to the length direction of the rotary arm supporting member, or wherein the rotary arm supporting member for supporting the rotary arm has a fixing rotary axis at one end thereof and is rotated in a center of the fixing rotary axis, and wherein the rotary arm supporting member includes a rotary driving means for rotary driving the rotary arm, and a means for driving the rotary arm to a length direction of the rotary arm supporting member