Pulmonary hairy glass nodules are not always malignant, they can also be benign, and most of them are benign. Inflammation, hemorrhage, infection, allergy, tuberculosis, and tumors can manifest as hairy glass nodules. Simple hairy glass nodules larger than 10 mm and mixed hairy glass nodules with solid components greater than or equal to 6 mm may be lung cancer with special signs lung hairy glass nodules suggesting possible lung cancer with burr, lobarization, pleural wrinkling, bronchial inflation signs, and even if they are lung cancer, most of them are early stage lung cancer. Pulmonary hairy glass nodule is a focal well-defined hyperdense shadow in the lung on CT scan, which is hairy glass-like and its density is not sufficient to cover the bronchial vascular bundles traveling in it.