The hard pimples on the feet may be corns, metatarsal warts and calluses. 1. corns: the disease often involves the palms of the feet, toes and the dorsum of the feet and other places, the clinical manifestation of the border is clear keratinous proliferation, inverted cone, there will be a thickening of the skin, accompanied by pain. The cause of the disease may be related to the long-term friction or pressure on the foot. 2. metatarsal warts: the patient foot will appear small shiny papules, with time to increase to the size of soybean or larger, and gradually formed yellowish, brownish-yellow plaque, the surface of the papillary hyperplasia. The onset of metatarsal warts is mostly related to HPV infection, and factors such as low immunity, long-term mechanical stimulation and sweaty feet may also induce the disease. 3. callus: common site for the hands and feet and other places, the patient’s skin will appear thickened, rough and hard, elevated plaque, mostly yellow, wax yellow. Its etiology is mostly related to the excessive proliferation of the stratum corneum, and factors such as frequent wearing of high heels or walking posture abnormalities may trigger the disease. There are many reasons that lead to very hard acne on the feet, and it is recommended that patients go to a regular hospital to clarify the cause of the disease and follow the doctor’s instructions for treatment.