An X-ray diagnostic apparatus comprises an X-ray tube and processing circuitry. The X-ray tube includes a rotary anode. The processing circuitry is configured to derive an acquiring condition from a fluoroscopic image, and start to increase, in accordance with the acquiring condition derived, a rotating speed of the anode from a low rotating speed to a high rotating speed before the X-ray tube finishes emitting an X-ray to acquire the fluoroscopic image.