There are two relatively common diseases that itch on the inner thighs, such as: i. Tinea corporis is a fungal infectious skin disease caused by dermatophytes invading the skin keratin. It mainly appears as a well-defined erythema at the root of the thigh or inguinal area, with a marked inflammatory reaction at the edge of the erythema and a tendency to heal in the center, which can be flaky. The diagnosis can be confirmed by fungal microscopy, and the mycelial structure can be seen under the microscope. Topical antifungal medications, such as naftifine ketoconazole cream and luliconazole cream, can be applied. Second, eczema, erythema in the thigh area, the boundary is not clear, more symmetrical appearance, fungal laboratory test under the microscope no fungal structure. The main topical application of anti-inflammatory and anti-allergic drugs, such as Denide cream, etc.