A smaller and smaller penis may be caused by lower androgen levels, obesity and other reasons. 1. Reduced androgen levels: the penis is getting smaller and smaller on the one hand and androgen-related, such as after the age of 50 with the reduction of androgen levels, the penis will gradually appear to reduce the size of the situation. 2. Obesity: the penis is getting smaller and smaller on the other hand is likely to be related to obesity, especially the male prepubic fat pad hypertrophy will bury the penis, manifested in the exposed part of the shrinkage. In addition, the penis is getting smaller and smaller there may be other reasons, if the phenomenon, should be timely hospital consultation, improve the relevant examination, clear the cause of the disease and actively comply with the doctor’s instructions for treatment.