According to one embodiment, An X-ray diagnostic apparatus includes an X-ray generator that generates X rays, an X-ray detector that detects the X rays generated by the X-ray generator and having passed through a subject, an X-ray restrictor that restricts an irradiation range on a detection surface of the X-ray detector of the X rays generated by the X-ray generator, a signal input unit that inputs a biomedical signal related to the subject, a signal detector that detects a biomedical change from the biomedical signal and also outputs an extension switching signal, and an X-ray restrictor controller that controls the X-ray restrictor such that the irradiation range of the X rays is extended in response to output of the extension switching signal.
