Feeling uncomfortable in the chest may be caused by digestive system diseases, cardiovascular diseases, respiratory system diseases and endocrine system diseases. 1. Digestive system diseases: if there is reflux gastritis, reflux esophagitis, chronic gastritis, gastric ulcer, etc., due to the lesions at the stomach and esophagus, it manifests as acid reflux, belching, gastric pain, etc., which in turn manifests as discomfort in the chest. 2. Cardiovascular system diseases: if there is angina pectoris, myocardial infarction, etc., it will also be manifested as chest discomfort, such as chest pain, chest tightness, chest tightness. For the combination of hypertension, diabetes, hyperlipidemia and other medical history of the population, more likely to appear. 3. Respiratory diseases: such as pleurisy, the inflammation involves the pleura, manifested as chest pain, chest tightness, etc., and the pain is aggravated by coughing or position change; tuberculous pleurisy is also accompanied by low-grade fever, night sweats and other systemic symptoms. 4. Endocrine system diseases: such as long-term mental stress, resulting in hormone secretion disorders, chest tightness and other discomforts. Such as hyperthyroidism and other diseases may appear such symptoms. Chest always feel uncomfortable can also be seen in other diseases, it is recommended that patients seek timely medical treatment, so as to avoid delaying the condition.