Left chin pain when pressed, may be caused by the following aspects: 1, may be trauma caused by local soft tissue contusion, this situation usually have a very clear history of trauma, such as being hit by someone, or local impact and caused, usually in addition to the pain, there will be localized swelling, or subcutaneous ecchymosis formation. 2, may be localized aseptic inflammation, it may be sleeping It may be aseptic inflammation caused by ischemia due to long-term compression during sleep, which can disappear naturally. If there is local redness, swelling, heat and pain, you can take oral non-steroidal anti-inflammatory drugs to reduce inflammation and relieve pain. 3, it may be the formation of enlarged lymph nodes in the jaw, this situation in the press or touch the jaw, you can feel the granular nodes, and when pressed, it will be painful, the most common is caused by acute pharyngitis, acute tonsillitis, oral ulcers.