Functional ED and organic ED are classified according to the etiology that leads to the occurrence of ED, which is currently the most commonly used classification method. Functional ED is the main reason for the occurrence of psychological disorders, no obvious organic lesions exist, but the command of sexual arousal – the sexual center, the inhibition of sexual arousal to strengthen the spinal erectile nerve center sexual arousal, so we are sometimes called psychogenic ED, psychological ED or psychogenic ED. And organic ED is caused by organic lesions, and usually according to its specific causes, it is divided into the following categories: 1, neurological ED: lesions and injuries to the brain center and spinal cord lesions, injuries, such as damage to the erectile nerve in patients with paraplegia, can lead to nerve disorders that conduct sexual excitement and cause ED. 2, vascular ED: the blood supply to the penis is very adequate, the penile blood vessels can be divided into The deep penile artery, superficial artery, deep penile veins and superficial veins, etc., and some vessels have special structures in order to adapt to the needs of penile erection. When the penile arteries and veins, damage or lesions, the penis can not be filled with blood erection, this cause of ED medical known as vascular ED. 3, endocrine ED: due to some lesions resulting in sex hormones, especially androgen levels are reduced or lack of ED, such as congenital anorchidism, pituitary tumors, etc. 4, drug ED: ED caused by taking certain drugs, such as antipsychotics chlorpromazine, Valium; anti-hypertensive drug reserpine, as well as anti-ulcer drug metformin and diuretics, such as Antiseptic.