Wearing a mask with a red rash on the face may be caused by contact dermatitis, acne aggravation, eczema and other reasons. 1. Contact dermatitis: the patient is allergic to the mask material, resulting in contact reaction after facial contact with the mask, manifested as itching, redness and pimples on the contact area with the mask. The patient should stop wearing the mask in time. 2. Acne aggravation: poor breathability of masks will lead to moisture and stuffy facial skin, pores are easily blocked and breeding bacteria, acne will be aggravated, manifested as red rashes on the face. Avoid wearing masks for long periods of time or replace them with more breathable masks. 3. Eczema: Wearing a mask will lead to poor facial breathability and localized moisture, easily complicated by eczema, manifested as localized itching and red rash, accompanied by liquid oozing. Wearing a mask face rash should go to the hospital in a timely manner, improve the examination, and give targeted treatment after the cause is clear.