An X-ray imaging apparatus comprising: an X-ray generator ; an X-ray detector ; a support that supports said X-ray generator and said X-ray detector while opposing said X-ray generator and said X-ray detector to each other; a turning driving unit that turns said X-ray generator and said X-ray detector supported by said support ; a head holder that holds a head (MH) of a subject (M1); a mode setting receiving unit that receives selection of a mode among a plurality of modes including a panoramic mode in which a curved section corresponding to a dental arch is imaged and a CT mode in which a predetermined imaging region is imaged; and an X-ray beam shape adjuster that adjusts a shape of an X-ray beam emitted from said X-ray generator according to the mode of which the selection is received by said mode setting receiving unit , wherein said X-ray beam shape adjuster shapes the X-ray beam into an X-ray cone beam (BX1) in which a center beam (XC1) that is a center of the X-ray beam is incident orthogonally to a body axis (BA1) of said head (MH) in said CT mode, characterized in that said X-ray beam shape adjuster shapes the X-ray beam into an X-ray narrow beam (BX2) in which a center beam (XC2) that is a center of the X-ray beam is incident upward from below with respect to said body axis (BA1), said X-ray narrow beam (BX2) having a length in a direction of said body axis (BA1), in said panoramic mode, and in that the X-ray imaging apparatus further comprises a magnification ratio changing mechanism that changes a magnification ratio by relatively moving said X-ray detector with respect to said head (MH) held by said head holder , wherein said magnification ratio changing mechanism decreases the magnification ratio in said panoramic mode as compared with the magnification ratio in said CT mode. an X-ray generator ; an X-ray detector ; a support that supports said X-ray generator and said X-ray detector while opposing said X-ray generator and said X-ray detector to each other; a turning driving unit that turns said X-ray generator and said X-ray detector supported by said support ; a head holder that holds a head (MH) of a subject (M1); a mode setting receiving unit that receives selection of a mode among a plurality of modes including a panoramic mode in which a curved section corresponding to a dental arch is imaged and a CT mode in which a predetermined imaging region is imaged; and an X-ray beam shape adjuster that adjusts a shape of an X-ray beam emitted from said X-ray generator according to the mode of which the selection is received by said mode setting receiving unit , wherein said X-ray beam shape adjuster shapes the X-ray beam into an X-ray cone beam (BX1) in which a center beam (XC1) that is a center of the X-ray beam is incident orthogonally to a body axis (BA1) of said head (MH) in said CT mode, characterized in that said X-ray beam shape adjuster shapes the X-ray beam into an X-ray narrow beam (BX2) in which a center beam (XC2) that is a center of the X-ray beam is incident upward from below with respect to said body axis (BA1), said X-ray narrow beam (BX2) having a length in a direction of said body axis (BA1), in said panoramic mode, and in that the X-ray imaging apparatus further comprises a magnification ratio changing mechanism that changes a magnification ratio by relatively moving said X-ray detector with respect to said head (MH) held by said head holder , wherein said magnification ratio changing mechanism decreases the magnification ratio in said panoramic mode as compared with the magnification ratio in said CT mode. <EOS>