The present invention provides an X-ray exposure area regulation method, a storage medium, and an X-ray system. According to one embodiment of the present invention, the X-ray exposure area regulation method comprises: monitoring the state of an obj ect under test (OUT) in real time and acquiring an initial image of the OUT when the state of the OUT satisfies the preset condition, determining an area of interest (AOI) in said initial image, and setting said X-ray exposure area based on the information of said AOI. The present invention can realize automatic regulation of an exposure area in the X-ray system according to the OUT. The present invention can not only facilitate operations and improve test efficiency, but also free patients from exposure to unnecessary radiations.