“Ringworm is a common name for a variety of fungal infections of the body surface. Ringworm on the face is clinically known as “tinea corporis” and is a special type of ringworm, mainly caused by ringworm infections of the epidermis such as Trichophyton rubrum, Trichophyton rubrum, Trichophyton verrucosum, and Microsporum canis. In general, the sebum secretion of facial skin is relatively strong, and the sebaceous film on the surface of the skin is decomposed by the normal parasitic flora of the epidermis to produce weak acids such as free fatty acids, which gives the facial epidermis a normal weak acidic state and can effectively inhibit the growth of various pathogenic epidermis ringworm bacteria. When the sebum secretion of the face is reduced due to over-cleaning and malnutrition, the normal sebaceous film is missing, and the bacteriostatic weak acidic environment is damaged, it will easily lead to “ringworm” on the face. On the other hand, when the immune function is low due to disease, medication, or other factors, immunosuppression or destruction of the normal parasitic flora of the face can also lead to the colonization of pathogenic S. epidermidis. In addition, although ringworm occurs on the face, it is difficult to distinguish it from dermatitis and eczema because the face is cleaned more frequently and contains abundant sebum, which is common in ringworm, and there are fundamental differences in the treatment of these two types of diseases. Therefore, when ringworm occurs on the face, it is best to have it diagnosed accurately by a professional dermatologist and, if possible, to have fungal microscopy and culture tests to find an objective basis to avoid misdiagnosis and mistreatment.