An X-ray photography apparatus, comprising: a support that supports an X-ray generator and an X-ray detector while said X-ray generator and said X-ray detector are opposed to each other so that a head of a subject to be photographed being interposed therebetween, a subject retention part adapted to fix the subject, the X-ray detector outputting an electric signal according to an intensity of an incident X-ray; a moving mechanism that includes a turning part and a moving part, wherein the turning part is configured to relatively turn said X-ray generator and said X-ray detector about said head by relatively turning said support relative to said head about a predetermined turning axis, wherein the moving part is configured to move said support relative to said head in a direction perpendicular to said turning axis; a photographic region designation part that is configured to designate part of a row of teeth along the dental arch of the interposed subject; an irradiation direction changing part that is configured to relatively change an irradiation direction in which said head is irradiated with the X-ray with respect to an axial direction of a body axis; and a controller that is configured to control said moving mechanism, to control said irradiation direction changing part for changing said irradiation direction and to execute a pseudo intraoral radiography being a radiography in the way of tomography, wherein said X-ray generator and said X-ray detector are rotated about said interposed part of the row of teeth as a pseudo intraoral radiography region being an imaging region equivalent to the imaging region of a conventional intraoral radiography, such that said pseudo intraoral radiography region is irradiated with X-ray beams according to a designation by said photographic region designation part, and to control the movement of said support and of said irradiation direction changing part based either on a previously determined inclination of a tooth axis of a tooth of a standard skeleton, or on a manually input setting of the irradiation direction. a support that supports an X-ray generator and an X-ray detector while said X-ray generator and said X-ray detector are opposed to each other so that a head of a subject to be photographed being interposed therebetween, a subject retention part adapted to fix the subject, the X-ray detector outputting an electric signal according to an intensity of an incident X-ray; a moving mechanism that includes a turning part and a moving part, wherein the turning part is configured to relatively turn said X-ray generator and said X-ray detector about said head by relatively turning said support relative to said head about a predetermined turning axis, wherein the moving part is configured to move said support relative to said head in a direction perpendicular to said turning axis; a photographic region designation part that is configured to designate part of a row of teeth along the dental arch of the interposed subject; an irradiation direction changing part that is configured to relatively change an irradiation direction in which said head is irradiated with the X-ray with respect to an axial direction of a body axis; and a controller that is configured to control said moving mechanism, to control said irradiation direction changing part for changing said irradiation direction and to execute a pseudo intraoral radiography being a radiography in the way of tomography, wherein said X-ray generator and said X-ray detector are rotated about said interposed part of the row of teeth as a pseudo intraoral radiography region being an imaging region equivalent to the imaging region of a conventional intraoral radiography, such that said pseudo intraoral radiography region is irradiated with X-ray beams according to a designation by said photographic region designation part, and to control the movement of said support and of said irradiation direction changing part based either on a previously determined inclination of a tooth axis of a tooth of a standard skeleton, or on a manually input setting of the irradiation direction.