Abstract: Thyroid papillary carcinoma pulmonary metastasis and bronchioalveolar carcinoma have similar biological and clinical characteristics. The treatment for each of these two conditions is different. They can be discriminated by clinical features, pathology and imaging. For patients who have nodules in the thyroid, lung, axillary nodes and lymph nodes of the neck, it is hard to determine whether the condition is thyroid papillary carcinoma pulmonary metastasis or bronchioalveolar carcinoma. We discuss a case to emphasize the importance of using a combination of clinical features, pathology and imaging in the differential diagnosis of the two conditions.