Ringworm is a fungal infection (commonly known as ringworm) that occurs in the femur (groin, perineum, etc.). The fungus likes dark, damp, nutrient-rich areas. The groin has many folds, and some people have ringworm because they are obese or have poor personal hygiene habits, and the area is damp, sweaty, and rich in oil, making it ideal for fungal growth. Topical antifungal creams, such as ketoconazole cream, butenafine cream, and terbinafine spray, are generally used for mild cases to improve the condition. It is important to improve the local humidity and hot environment, such as taking more baths, using prickly heat water and zinc oxide ointment to keep the area dry, and for obese people to lose weight and wear loose cotton sweat-absorbing underwear. Pay attention to the disinfection and sterilization of contaminated supplies (hot water boiling is recommended because of the strong survival ability of spores). The general treatment course is 2-4 weeks, the symptoms can disappear in 2 weeks, consolidate to 4 weeks to prevent recurrence. If treatment is not effective, consider combining oral antifungal medications. Itraconazole capsules or terbinafine tablets are recommended, both are prescription medications and need to be used under medical supervision for a 1-2 week course of treatment. Ringworm is one of the most common fungal infections of the skin. Standardized treatment and a high cure rate, with attention to lifestyle, can effectively reduce the recurrence rate.