Psoriasis, also known as psoriasis, is a polygenic hereditary disease caused by the interaction of many factors such as genetic factors and environmental factors. It is often seen that a family has many patients over several generations, and it is also seen that identical twins suffer from psoriasis at the same time. About 20-30% of patients have a clear family history, and some families have a clear genetic predisposition, which indicates that psoriasis is related to genetic factors. The fact that psoriasis has a genetic tendency does not mean that children are born with psoriasis, but that children with a family history of psoriasis are more susceptible to psoriasis than other children under the action of environmental factors, and clinically a large proportion of patients do not have a family history. The causes and triggering factors of psoriasis are not yet clear, and the disease has a long course and a tendency to recur. Drugs, infection, cold stimulation, pregnancy, diet, mental, trauma or surgery may trigger or aggravate psoriasis. Some patients with light psoriasis may heal themselves by avoiding the triggering factors; pan-plaque psoriasis, pustular psoriasis, arthritic psoriasis and erythrodermic psoriasis basically cannot heal themselves, but need to go to the hospital for standardized treatment, and improper treatment or untimely treatment may aggravate psoriasis and even endanger life with electrolyte disorder, hypoproteinemia, secondary infection and liver and kidney function damage.