The present application discloses a method for detecting foreign objects in a cover glass module and a related device, which are used to improve the detection accuracy of foreign objects in the cover glass module. The method of the present application includes: setting a camera, a cover glass module, and a light source; turning on the second light source to take pictures of the cover glass module; turning on the first light source to take pictures of the cover glass module; performing median filtering on images I0, I1 and I2; Image IF0, image IF1, and image IF2 are subjected to gray-scale morphological bottom-hat transformation and binarization processing; image I1 and image I2 are respectively subjected to gray-scale morphological top-hat transformation and binarization processing; Perform OR, AND processing, and morphological reconstruction of the four foreign object images, the second foreign object image, and the third foreign object image; perform OR, AND processing, and size selection on the first foreign object image, image IF1, second foreign object image, and image IF2 Processing and morphological reconstruction; generation of OCA dissection foreign body images and screening detection.