A red mark on the face may be caused by nevus erythematosus, seborrheic dermatitis or lupus erythematosus, etc. The patient can be treated by laser, surgery, topical application of medication and oral medication according to the doctor’s instructions. 1. Nevus erythematosus: this disease is a congenital capillary malformation, manifested as light or dark red patches of varying sizes and clear boundaries on the face, neck and other parts of the body. In the treatment, you can follow the doctor’s advice to choose laser treatment, photodynamic therapy and surgical treatment and other methods to eliminate. 2. Seborrheic dermatitis: patients with seborrheic dermatitis may have red spots on the face, greasy scales, etc., and after removing the scales, light red marks can be seen. In the treatment can be prescribed topical glucocorticoid drugs, calcium-modulated phosphatase inhibitors, etc., and in severe cases, oral antihistamine drugs and other treatments. 3. Lupus erythematosus: it belongs to autoimmune disease, manifested as butterfly-shaped erythema on cheeks, and patients can also be accompanied by other systemic injuries. Patients should take oral glucocorticosteroids and immunosuppressants as prescribed by the doctor for treatment after a comprehensive systematic examination. It is recommended that patients with a red mark on their face go to the hospital in time to clarify the cause of the disease and under the guidance of the doctor to carry out targeted treatment.