Most of the warts on the hands are common warts, caused by human papilloma virus infection of the skin and mucous membranes, with a certain degree of contagiousness, with the body of low immunity, direct or indirect contact with viruses and other factors; a small number of flat warts, caused by the human papilloma virus (HPV) 3 infections, with low immunity, trauma and other factors. 1. Common warts (1) low immunity: when the body’s immunity is low, the skin and mucous membranes of the traumatized skin are more likely to develop after coming into contact with the human papilloma virus. (2) direct or indirect contact with the virus: if the broken skin directly contact with the human papilloma virus, or with patients suffering from common warts share personal belongings, etc., easily infected with human papilloma virus and suffer from common warts. 2. Flat warts (1) low immunity: long-term fatigue, lack of sleep, malnutrition, their own diseases, etc., will lead to a decline in immunity, when the body is more likely to be attacked by the human papilloma virus, thus flat warts. (2) trauma: skin trauma, after contact with the human papilloma virus, replication, proliferation in the body, resulting in excessive proliferation of epithelial cells and hyperkeratosis, the accumulation of these cells together, will be formed on the surface of the skin flat protruding small bumps. It is recommended that after diagnosis, patients should go to regular hospitals for timely consultation and treatment to avoid delaying the condition. Usually pay attention to rest and avoid skin breakage.