An X-ray diagnostic apparatus according to an embodiment includes processing circuitry. The processing circuitry is configured to measure respective profiles on contrast media concentration in regions of interest including blood vessels set at about the same position in two subtraction images of subject's head taken from about the same direction at different radiography times. The processing circuitry is configured to determine a correction factor so that the two profiles measured are approximately matched. The processing circuitry is configured to correct at least one of the two subtraction images on the basis of the correction factor determined. The processing circuitry is configured to control so as to display information based on the two subtraction images that at least one thereof has been corrected on a display.