A painful bump on the back of the head that hurts when pressed needs to be treated based on the cause. There are many causes of pain behind the head, generally considered folliculitis, scalp hematoma, sebaceous cysts secondary infection and other causes. 1. Folliculitis: due to the inflammation of a single hair follicle, can be manifested as scalp follicles with bumps accompanied by redness, swelling and pain. Can use ichthyolite ointment, erythromycin ointment and other drugs for local application, serious symptoms can be oral amoxicillin capsules, cefaclor and other antibacterial drugs. 2. Scalp hematoma: due to trauma, can lead to scalp subcutaneous bruising and long bag with pain. Most can be self-absorbed, hematoma can be extracted by the doctor puncture and other methods of treatment, if there is a combination of the formation of infected abscesses need to be incised by the doctor to drain. 3. Sebaceous cysts secondary infection: Due to the blockage of sebaceous ducts in the skin, sebum gradually accumulates and forms retention cysts. It can be treated by surgical excision, etc. Secondary infection can be treated with antibacterial drugs (e.g. cefixime tablets, amoxicillin capsules, etc.). Patients need to go to the hospital to clarify the cause of the disease, the drug has certain side effects, should be applied under the guidance of the doctor, they can not randomly use drugs.