The application of industrial X-ray CT testers in infrared focal plane detectors is introduced. The CT can be used to non-destructively analyze the dewar components and refrigerators, especially to detect internal structural faults and defects. It can improve fault analysis ability and the efficiency of solving problems, which provide sufficient basis for component rework. In the following work, qualified samples can be selected according to the demand.This improves the user experience of the product and is an important guarantee for the subsequent production process.