Penis 3 fingers thick is a normal phenomenon, if the penis exists to continue to increase or accompanied by other abnormal phenomena, is abnormal. 1. Normal phenomenon: most men’s penis is completely weak, the diameter of 1.9 ~ 4.3 cm or so, fully erect, the diameter will be slightly thicker, but there are individual men, the penis is naturally thicker, even in the weak, the diameter of the three fingers thick, if the body does not have other abnormalities, it is a normal situation. 2. Abnormal phenomenon: If the adult penis has been normal before, late growth to three fingers thick, and has continued to grow, the body may exist in the anterior pituitary overdevelopment and other abnormalities, is abnormal phenomenon. The body appears abnormal phenomenon, it is recommended to go to the regular hospital in a timely manner, with the help of professional doctors, standardized treatment, so as not to delay the condition.