A hard lump on the bottom of the foot hurts when pressed, often due to the following reasons: 1. corns, because the plantar area of the foot is prone to repeated pressure, so it may grow corns, need to go to the hospital general surgery or hand and foot surgery for clarification. If the disease, the corns can be removed under local anesthesia, and then given sutures and regular drug changes at a later stage; 2, it may be caused by a foreign body piercing, which needs to be examined by the hospital’s surgery or emergency department. If an obvious foreign body can be found, the foreign body can be removed, and if necessary, local tissues need to be removed and sutured; 3, it may be caused by local infection, which requires the use of topical anti-inflammatory drugs, such as iodophor or Bactrim, and if necessary, oral antibiotics for treatment; 4, there are also some patients caused by local osteophytes, and need to go to the orthopedic department to take X-rays for clarification.