Retracted testicles are usually normal physiological phenomena, but they can also be caused by diseases, such as cryptorchidism, sliding testicles, and so on. The sub-scenarios are as follows: 1. Testicular contraction generally belongs to normal physiological phenomenon, such as in the case of cold, panic and pain, the levator muscle is over-contracted, causing testicular contraction, if there is no special discomfort, there is no need for special treatment. 2. If the testicles are often in a contracted state, the testicles cannot be touched in the scrotum, and the testicles are in the groin or the entrance of the scrotum, it means that the descent of the testicles is incomplete, which belongs to cryptorchidism, and it should be treated by surgery. Because the temperature of these areas is 1.5 to 2 degrees higher than that of the scrotum, which will affect the normal spermatogenesis of the testicles and may lead to infertility, which needs to be clearly diagnosed through ultrasound examination. 3. Testicular mobility is relatively large, which can descend into the scrotum or retract into the groin. This condition is called sliding testis, which requires testicular descent and fixation surgery to fix the testis in the scrotum. If symptoms persist for a long time without improvement, early medical treatment is recommended.