Large testicles in the elderly are considered to be related to orchitis, epididymitis, testicular torsion, syringomyelia, and testicular tumors. 1. Testiculitis: the disease is related to bacterial, viral and other pathogenic infections. The common symptoms of patients include high fever, chills, enlarged testicles, testicular pain and so on. When the old man suffers from orchitis, the phenomenon of large testicles can be induced. 2. Epididymitis: Epididymitis is related to bacterial infection, urine reflux, bad sexual behavior and so on. Typical symptoms of patients include pain or swelling in the epididymis area, limitation of movement, frequent urination, urgency of urination, lower abdominal pain, etc., which can be manifested as large testicles. 3. Testicular torsion: the etiology of testicular torsion is still unclear, which may be related to testicular dysplasia, testicular tunica vaginalis and so on. The disease may cause testicular pain, redness and swelling of the scrotal skin, enlarged testicles and other symptoms in some patients. 4. Syringomyelia: testicular syringomyelia is related to chronic inflammatory stimulation, developmental delay, etc., which can be manifested as enlargement of scrotal contents and a sense of falling and pain, and some patients do not have obvious self-awareness of symptoms, which can cause testicular enlargement in some elderly people. 5. Testicular tumor: the cause is unknown, which may be related to cryptorchidism, orchitis, genetic abnormalities and so on. Testicular tumor: the cause is unknown, may be related to cryptorchidism, orchitis, genetic abnormalities, etc. Diseases can cause testicular enlargement in the elderly, and it is easy to be accompanied by other symptoms such as dull pain in the scrotum and lower abdominal swelling. Part of the elderly testicles are normal phenomenon, if accompanied by other uncomfortable symptoms, should be timely medical examination, in order to clarify the cause of the disease, and then follow the doctor’s instructions for treatment.