Impotence is the most common male sexual dysfunctional disease, or ED for short, which refers to a man’s inability to achieve or maintain a sufficient erection during sexual intercourse to complete a satisfactory sexual life, and the duration of the disease lasts for more than three months. The main manifestation is slow or difficult erection at the beginning of sexual intercourse; sometimes, although erection is achieved, the erection is not hard enough to cause difficulty in penetration or cannot be inserted into the vagina at all. Impotence is usually associated with cardiovascular disease, hyperlipidemia, diabetes mellitus, hypothyroidism, androgen deficiency, hyperprolactinemia, hyperestrogenemia, obesity, long-term heavy smoking, alcohol abuse, and lack of exercise. The incidence of impotence gradually increases with age, with the incidence of impotence exceeding 50% in adult men over the age of 40. It is now initially divided into three main categories: psychological, organic and mixed. What tests should be performed to diagnose ED? 1, comprehensive physical examination, focusing on the genital organs. 2, blood and urine routine, liver and kidney function, blood sugar and lipids, sex hormone levels. 3, penile erectile hardness analysis, nocturnal penile erection record, Doppler ultrasound blood flow test. 4.Special examination: pubic A and penile cavernosography, neuromyography, cavernosal biopsy.