Many people have a very strong fear of patients with skin diseases, and as soon as they say skin diseases, they subconsciously think that they are contagious, which is one of the reasons why many psoriasis patients are suffering. In fact, psoriasis is not contagious. Heredity is one of the causes of psoriasis, but this does not mean that if the parents have psoriasis, the child will definitely get psoriasis, but also under the superposition of environmental factors before it happens. The role of the environment on psoriasis mainly refers to infection and stress. By infection, we mean infection of the upper respiratory tract or dysbiosis of the skin flora itself, while stress factors mainly include anxiety, stress and severe lack of sleep. Current medical research confirms that psoriasis is not caused by direct infection by pathogenic bacteria, i.e. it is not directly caused by bacteria, fungi or parasites. Therefore, psoriasis is not an infectious disease. Psoriasis is not contagious and will not infect people. Patients with psoriasis should have confidence, actively treat it, follow medical advice and do a good job in daily care, and their relatives and friends should also give more respect and care.