The cause of total penile erection may be related to drug effects, hematologic disorders, neurological disorders or reproductive system pathologies. 1. Drugs: some drugs can affect the nerve smooth muscle to induce abnormal erection, mainly systemic application of antipsychotics, sedatives, antihyperlipidemics, etc., especially vasoactive drugs injected into the penile corpus cavernosum to treat erectile dysfunction. 2. Blood system diseases: such as sickle cell hemoglobinopathy, leukemia, multiple myeloma, primary thrombocythemia. All of them may cause abnormal erection of the stem. 3. Neurological diseases: central nervous system diseases, such as epilepsy, cerebral aneurysm rupture. Abnormal penile erection can also occur in patients with intervertebral disc herniation, lumbar spinal stenosis and a very small number of patients with spinal stenosis or tumors compressing the spinal canal. 4. Reproductive system diseases: primary or secondary to the external genital organs and pelvic organs of the tumor encroachment on the cavernous body or compression of the pelvic blood vessels leading to impaired venous return to the penis, causing abnormal penile erection. It is recommended that patients go to regular hospitals for treatment in time to avoid serious consequences.