Penile atrophy becomes smaller hard not to get up is mostly caused by mental psychological factors, penile cavernous blood flow abnormalities, pelvic floor nerve damage and other reasons. 1. Spiritual psychological factors: refers to the daily husband and wife relationship disharmony, sexual knowledge asymmetry or lack of, adverse sexual experience, work or economic pressure, incorrect understanding of the media propaganda, the disease and drug adverse reaction, such as the emergence of nervousness, stress, depression, anxiety or fear, leading to the emergence of penile atrophy become small hard to get up in the sexual life. 2. Atherosclerosis, arterial stenosis, arterial damage, perineal arterial shunt will make the penile corpus cavernosum blood flow abnormality, blood can not quickly enter the penile corpus cavernosum during sex, the penis can not harden and become long and appear penile atrophy small hard not up situation. You should have your blood sugar and lipids checked in time to find out the cause of the disease and treat it. 3. Pelvic floor nerve injury: prostate cancer radical surgery, pelvic floor radiotherapy or pelvic trauma may lead to peripheral nerve injury, such as pubic nerve, triggering the phenomenon of penile atrophy. In daily life should develop good habits, avoid excessive frequent masturbation, avoid overwork, avoid staying up late, prohibit smoking and alcohol, reasonable diet, such as penile atrophy small hardness for a long time without relief, should be early medical treatment.