Abstract: Core positioning detection technology is a key method to ensure product quality. In order to meet the requirements of engineering applications, X-ray digital imaging technology, mechanical motion mechanisms (including automatic feeding and unloading, X-ray scanning motion mechanisms, etc.), image processing algorithms (including image distortion correction, core contour and discrete particle identification), core positioning algorithms, etc, an automatic core positioning system for plate fuel element core boundary recognition is established, and the detection equipment is developed to realize the automatic core positioning detection of plate fuel element.