The appearance of hard bumps on the soles of the feet should actually refer to the local occurrence of a significant proliferation of the stratum corneum. However, the appearance of this situation should be carefully analyzed, first of all, the patient may be due to the skin of the foot is repeated pressure, friction caused by the thickening of the stratum corneum, such as callus is such a situation. But there are also patients who have a hard lump on the sole of the foot, which appears to have thickened stratum corneum, but is actually a common benign epidermal growth due to human papillomavirus infection. Repeated rubbing of this growth can also produce a marked thickening of the stratum corneum. However, it is often difficult to differentiate between a callus and a plantar wart. So if the patient in the soles of the feet appear hard bumps, it is best to go to the regular hospital dermatology department in time, callus in the clinic often does not appear to be obvious more situations. But plantar warts, if not treated in a timely manner, will appear to increase significantly and become larger.