A very large hard pimple on the chin may be related to conditions such as folliculitis, boils, sebaceous cysts, etc. It is necessary to clarify the cause of the condition and deal with it through medication (erythromycin ointment, etc.) or surgical treatment. 1. Folliculitis: This is caused by a bacterial infection, and will result in redness, swelling and pain. It can be treated by applying erythromycin ointment, together with oral medication such as cefprozil dispersible tablets and azithromycin dispersible tablets. 2. Boils: there are obvious bumps and pain, need to apply ichthyol ointment, fusidic acid cream and other drugs, if necessary, the boils can be removed. 3. Sebaceous cysts: Cysts formed when sebaceous glands do not drain well and become clogged, and may have small black dots in the center. Surgery is needed to remove the cyst. A very large hard pimple on the chin, due to a variety of causes, it is recommended to consult a doctor in a timely manner, to clarify the cause of the disease, and then strictly comply with the doctor’s instructions for treatment.