The main causes of enlarged anterior mediastinal lymph nodes are inflammation, lymphoma, tumor metastasis and other conditions. Lymph nodes in the human body are part of the lymphatic system, which mainly plays a role in enhancing immunity, suppressing inflammation, and preventing the spread of infection, etc. When there is localized inflammation or infection foci in the human body, the lymph nodes around the foci will increase in size. There are two main types of enlarged lymph nodes in the anterior mediastinum, namely, localized inflammation or infection around the anterior mediastinum and neoplastic diseases. Inflammation or infection is more common, and most of them may be combined with related symptoms, such as fever and effusion; while neoplastic diseases may originate from metastasis of malignant tumors in the thoracic cavity or lymphoma, and most of them are manifested as symptoms of tumor compression, infiltration, and wasting. It is recommended to consult a doctor in time when the enlargement of anterior mediastinal lymph nodes is detected, so that the cause of the disease can be clarified by a professional doctor with the combination of symptoms and relevant examination results, and symptomatic and causative treatments can be provided.