Frosted glass shadows in the lungs can develop for a variety of reasons, including infectious and non-infectious diseases. Milled glass shadows in the lungs refer to a symptom of lung imaging, such as CT of the lungs, where there is a mild increase in density on the image, but the bronchial vascular bundles within can still be shown, and are usually caused by lung diseases, including infectious and non-infectious diseases. Infectious diseases commonly include pneumonia and lung abscess, and non-infectious diseases commonly include interstitial fibrosis and lung cancer. Ground-glass shadow of the lungs is of great significance in clinical practice, which helps to diagnose lung diseases at an early stage and provide targeted treatment to avoid further aggravation of the condition.