Mediastinal tumors are a group of tumors originating in the mediastinum, including thymoma, intrathoracic goiter, bronchial cyst, dermatoid cyst, teratoma, lymphosarcoma, malignant lymphoma, pericardial cyst, lipoma, neurogenic tumors, and esophageal cyst, with benign ones being the most common. Teratomas are mostly seen below the age of 30 years, and the rest occur more often above the age of 40 years. Most mediastinal tumors except lymphosarcoma and malignant lymphoma have good prognosis. Surgery is the main treatment method. Primary mediastinal tumors, no matter benign or malignant, should be surgically resected as early as possible once discovered. Other treatments include chemotherapy, radiotherapy, traditional Chinese medicine and biotherapy. Acute anterior mediastinal abscess is rare in clinic, and it is a rapidly developing and fatal disease, with a case fatality rate of 40%~50%. Downward spread of infection in the parapharyngeal space, retropharyngeal space, and floor of the mouth is a common cause of acute anterior mediastinal abscess. The anatomy of the neck is complex, with the main anterior tracheal hiatus, visceral vascular hiatus and posterior visceral vascular hiatus, which contain loose connective tissue and abundant blood vessels internally, and between the trachea, esophagus and large blood vessels are filled with loose connective tissue and a large amount of lymphatic tissue, and upwardly connected to the cervical fascial hiatus. Infected foci can easily spread, and due to negative intrathoracic pressure and gravity the neck abscess can easily spread downward and involve the mediastinum or the thoracic cavity, and what we call the anterior mediastinum is the anterior tracheal space. The complex pathophysiologic changes and neuroreceptor involvement in the mediastinum as well as the involvement of many vital organs in the mediastinum lead to serious consequences. Massive absorption of bacteria and toxins leads to systemic toxic symptoms. Therefore, the possibility of mediastinal infection and pyothorax should be considered in those with a history of sore throat with neck swelling and chest symptoms. Routine chest X-ray or CT is effective in showing early mediastinal infection, determining the extent of surgical drainage and tracking the outcome. Surgical drainage and removal of necrotic tissue are important means of treatment, and effective antibiotics should be applied to control sepsis. Abscesses are mostly mixed infections of aerobic and anaerobic bacteria. Broad-spectrum antibiotics and anti-anaerobic drugs are preferred, and then the application of antibiotics should be adjusted according to bacterial culture and drug sensitivity test. Due to the large blood vessels and important organs in the mediastinum, the tissue edema is obvious when infection occurs, the operation should be gentle and careful, and the drainage material should be soft, so as to avoid abrasion of the large blood vessels, resulting in rupture of blood vessels and hemorrhage and damage to other organs.