Tinea corporis and tinea cruris are both caused by fungal infections, and the fungi responsible for these diseases are essentially the same. The main route of infection is direct contact. For example, frequent visits to public baths for soaking or swimming, or sharing items like bath scrubbers and towels. Additionally, some patients have athlete's foot and wash their socks together with their underwear, without proper sun exposure and disinfection, leading to cross-contamination. Therefore, after recovering from this condition, it is crucial to regulate diet and lifestyle habits, and eliminate as many risk factors as possible. Avoid going to public baths for soaking or swimming, wash underwear and socks separately, do not share bath scrubbers and towels, and bathe more frequently.