Hard skin bumps can be caused by boils, dermatofibromas, epidermal cysts and other diseases, which can be improved by medication, physical therapy, surgery and other ways. 1. Boils: If boils are the cause of hardened skin bumps, ichthyol ointment can be used externally for patients who do not have pus. For patients with large skin lesions or ineffective local treatment, drugs such as amoxicillin and azithromycin can be taken orally. 2. Dermatofibroma: skin long bumps hard to consider and dermatofibroma, patients can choose carbon dioxide laser treatment, the lesions will be removed, but also through the way of surgery will be directly excised tumor. 3. Epidermoid cysts: Epidermoid cysts may also cause hard skin bumps and are usually treated with surgery. For smaller cysts, patients can have them surgically removed directly. When a cyst becomes infected with pus, incision and drainage can be used to remove the contents of the cyst. For patients with hard skin bumps, it is recommended to go to a regular hospital for examination and treatment under the guidance of a doctor.