A hard bump on the foot that hurts when pressed can be caused by boils, corns, plantar warts and other causes. 1. Boils: an inflammatory disease caused by bacterial infection of the hair follicles on the feet and the surrounding tissues, clinically manifested as one or more red, hemispherical painful nodules, nodules in the center of the pus head. There will also be a hard bag on the foot that will hurt when pressed. 2. Corns: Corns, also known as thorns, usually occur on the toes and the front of the soles of the feet. Due to the long-term friction of the skin on the feet, the keratinization of the hyperplasia, manifested in the local raised conical corns, and there will be a painful phenomenon of pressure. 3. metatarsal warts: triggered by the skin infection of human papilloma virus on the feet, it will lead to the proliferation of the stratum corneum of the infected area, papilloma-like changes, the formation of warts, and prolonged friction will also appear to squeeze the painful situation. This is why there is a hard bump on the foot and it hurts when pressed. If you have a hard bag on your foot that hurts when pressed, you should go to the hospital in time and follow the doctor’s instructions for examination and treatment, so as not to delay the condition.