Seborrheic dermatitis is not necessarily a sign of HIV infection; seborrheic dermatitis is not a specific symptom of HIV. However, AIDS patients are more likely to develop seborrheic dermatitis than normal people. The cause of seborrheic dermatitis is not yet fully understood, and is currently thought to be related to abnormal sebum secretion, Malassezia infection, immune factors, damage to the epidermal barrier, age, heredity, environment, diet, and so on, and it may be that a combination of factors is involved in causing the disease. AIDS is infected with human immunodeficiency virus (HIV) through various ways, which violates the human immune system and leads to defective immune function of human cells, causing various opportunistic infections and tumors, which are contagious. AIDS patients are susceptible to skin diseases due to decreased resistance due to immune factors, and are more prone to seborrheic dermatitis than normal people. Seborrheic dermatitis is not directly related to AIDS, seborrheic dermatitis is a common skin disease, not a specific symptom of AIDS. If there has been a high-risk contact with AIDS, or suspected of infection, should be timely around the regular hospital or CDC testing.