The causes of purple glans in men are physiologic and pathologic, and pathologic factors include glansitis, phimosis, etc. Treatment includes medication such as antibiotics and surgery. 1. Physiological factors: with age, the function of various organs of the body gradually decline, the elderly are prone to glans weakness, purple and other symptoms. In addition, the lower temperature of the external environment can also cause the symptoms of black and purple in various parts of the body. 2. Pathological factors: microorganisms and other factors lead to glans inflammation will stimulate the blood circulation of the glans, thus appearing the glans black and purple, erythema and other symptoms. In addition, the prepuce will lead to the glans blood stagnation and thus the symptoms of black purple. When the patient is not feeling well, he should go to the hospital immediately.