An X-ray CT apparatus comprises three X-ray generating units, three groups of detecting elements and a reconstructing unit. The three X-ray generating units are arranged so as to make an angle formed by a first X-ray exposure direction and a second X-ray exposure direction on a rotational plane thereof be a same angle as that formed by the second X-ray exposure direction and a third X-ray exposure direction on the rotational plane, the same angle being smaller than 120 degree. The three groups of detecting elements are arranged opposite to the three X-ray generating units respectively so as to make a field of view formed in a center wider than two side fields of view. The reconstructing unit is configured to reconstruct an image using detection data detected by at least desired one of the three groups of the detecting elements.