Impotence is now referred to as erectile dysfunction due to the fact that it carries a certain amount of discrimination. Impotence in the traditional sense is actually the most serious kind of erectile dysfunction, and it is diagnosed with three criteria: First, the patient must have repeated sexual intercourse several times within three months, and the penis cannot be erected and inserted into the vagina during sexual intercourse before it is diagnosed as erectile dysfunction. Second, some relevant examinations need to be done, such as palpation of the external genitalia to observe whether there are congenital diseases, such as short penis and missing testicles, and also biochemical complete tests to detect blood sugar, blood lipids, liver function and kidney function, through which to determine whether there are organic diseases. If the hospital has special conditions, it can also do some non-invasive tests, such as the nocturnal penile distension test and penile ultrasound, and if the diagnosis is related to the disease, it is called organic impotence. Third, the diagnosis of impotence must do detailed communication and explanation with the patient to help him analyze the causes of erectile dysfunction. If impotence occurs because of emotional tension, physical fatigue, marital discord or induced by wrong sexual knowledge, and one describes normal night erection and normal morning erection, most people are caused by psychological factors and call it psychological erectile dysfunction.