Painful sensation in the left chest when taking a deep breath needs to be treated after a clear diagnosis, most people do not need to be treated, in a few cases may need to be treated with appropriate painkillers. Possible causes of pain in the left chest: local inflammation, pleurisy, intercostal neuritis, pneumothorax, breast disease, emotional tension or excitement and other conditions, deep inhalation when the stimulus effect is enhanced and pain. Deep breathing with pain in the left chest most due to a variety of stimulating factors do not last, such as a variety of inflammation or new organisms with respiratory movement and intermittent stimulation of the peripheral nerves, intercostal neuritis tingling, at this time, most of the pain can be tolerated, can not be dealt with, in order to clarify the cause or causative factors and to remove these factors are the main. In patients with pneumothorax, the expansion of alveoli during inhalation causes nerve irritation around the rupture, resulting in aggravation of pain. A small amount of pneumothorax should be treated with rest, while a large amount of pneumothorax requires puncture and suction or continuous closed drainage of the chest cavity, and those with recurrent pneumothorax require surgical resection of the diseased location. Breast inflammation or cysts, etc., pleurisy patients with deepening breathing movement, inflammatory tissue is pulled to stimulate the aggravation of pain, it is necessary to clarify the condition, appropriate anti-inflammatory, analgesic treatment, if necessary, surgical resection of the lesion. Deep breathing pain in the left chest has more causes, normal people also occur from time to time, but some may be disease manifestations, it is recommended to the regular hospital thoracic surgery consultation and treatment.