Hard bumps on the back of the feet are considered in the following three conditions: The first condition is a nodular itchy rash. It can appear as a hard, round papule with a brown or dark brown texture. In clinical treatment, strong glucocorticoid ointments such as halometasone ointment or fluticasone propionate ointment can be applied, and freezing can also be used for treatment. The second condition is common warts, which can appear as grayish brown or dark brown papules, soybean to bean in size, hard in texture, and slightly manicured. It can be treated with freezing or electro-ionic surgery or carbon dioxide laser cautery. The third type is dermatofibroma, which can be treated by surgical excision.