After infection with AIDS, it can cause the body’s immune function to decline, in the course of the disease, the skin and mucous membrane can appear a variety of lesions, such as non-infectious skin damage, infectious skin damage or skin tumors, etc. can appear red rash. 1. Non-infectious skin damage: the skin lesions are various, similar to psoriasis-like lesions, but also erythema multiforme, pityriasis rosea and other lesions, and a red rash can appear on the inner thighs. 2. Infectious skin damage: due to the decline in body resistance, various pathogen infections can occur, such as in fungal infection, can be generalized ringworm, red papules, papules or blisters appear on the skin. 3. Skin tumor: for example, Kaposi’s sarcoma, can be seen in the limbs, trunk and other places, skin lesions initially pink rash, later the color can gradually become lighter, can become hemorrhagic lesions and nodules. HIV prevention is the key, but after HIV infection, we should seek medical treatment in time to improve the quality of survival of patients.