Stabbing pain in the left chest for a few seconds and then disappears may be caused by intercostal neuralgia, angina, lung disease and other causes. 1. Intercostal neuralgia: It is a band of pain that extends from the spinal cord in the chest on both sides, through the intercostal space to the front wall of the chest. It is usually a radiating pain that stings for a few seconds and then disappears. 2. Angina pectoris: angina pectoris is caused by the contradiction between blood supply and demand in the coronary arteries. The blood flow in the coronary arteries is not enough to maintain its normal metabolism, which leads to transient ischemia and hypoxia of the heart, and then leads to angina pectoris, with the symptom of a stabbing pain for a few seconds and then disappears. 3. Lung disease: Diseases of the left lung, including infection, tuberculosis, tumors of the left lung, can lead to a stabbing pain in the left side for a few seconds and then disappear. Left chest pain for a few seconds and then disappeared may also have other reasons, it is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease, give targeted treatment or treatment, under the guidance of the doctor for treatment.