Abstract: Since the electromagnetic current transformer is a fully enclosed structure, its internal defects can not be visually shown by using conventional method in the case of failure. Using the X-ray digital imaging technology can show the internal structure of the 35 kV electromagnetic current transformer, and also can discover the physical defects of its existence. After the disintegration, we could verify the type of defects. The experimental results have shown that, compared with other conventional methods for detecting the X-ray digital imaging technology can be more intuitive in finding the location of the defect, and can be used to achieve the visualization of the internal structure of 35kV current transformer without disintegrating and destroying the main insulating, and it can accurately determine the defective nature, extent and type.