The scrotum is always tightly shrunk together can be caused by cold stimulation, trauma, cryptorchidism and other factors. 1. Cold stimulation: the scrotum local warmth is insufficient, the weather is cold, or when taking a cold shower, it can lead to cold stimulation of the scrotum area, resulting in the scrotum area of the blood vessels undergo sharp contraction, which can cause the scrotum to tightly contracted together performance, generally belong to the normal physiological phenomenon. 2. Trauma: when the scrotum is traumatized, the soft tissue of the scrotum can be damaged, and the local pain and swelling can occur, and when the damage is serious, the scrotum can be tightened. 3. Cryptorchidism: Cryptorchidism caused by heredity, growth and development, environmental factors, etc., may appear scrotal emptiness, dysplasia and other manifestations, and may appear scrotal tightness. When the scrotum is always tightly shrunk together, you should consult a doctor in time, under the guidance of a specialist to actively carry out appropriate treatment, which will help to alleviate the uncomfortable symptoms as soon as possible.