The soles of the feet itch when they are hot, consider and tinea pedis, senile itchy skin, eczema and other factors related. 1. Tinea pedis: Tinea pedis, also known as foot fungus, is a skin disease caused by fungal infection. The fungus survives and reproduces in hot and humid environments, and the increased number of fungi irritates the skin, leading to localized itching and possibly peeling and pain. 2. Geriatric itchy skin: dry dermatitis is a common cause of geriatric itchy skin, with age, skin atrophy and decreased blood supply to the skin, changes in lipid composition, impaired moisturizing function, scales, lower limbs are more common, itchy when the hot and cold changes are visible, especially in winter. 3. Eczema: Itching when the feet are hot can also be considered and eczema. For example, frequent wearing of breathable shoes, hot water scalding, intake of allergy-inducing food, resulting in inflammation of the superficial dermis and epidermis, which can cause redness, swelling, itching, or pimples, papules. Warmth on the soles of the feet and the beginning of itching may be caused by a variety of diseases (e.g. hyperthyroidism, dryness, urticaria, etc.). It is recommended to go to the dermatology department of the hospital to clarify the cause before making an appropriate treatment plan.