Recently, a 30-year-old man came to the clinic with the question, “Why is my scrotum always sweating and feeling uncomfortable? What’s going on?” During the physical examination, we found that the patient could feel tortuous and dilated veins in both scrotums, and the varicose veins became more obvious after the patient held his breath to increase the abdominal pressure, while the varicose veins decreased when he was lying down. I initially considered the varicocele to be bilateral and ordered the patient to undergo an ultrasound examination of the scrotal contents to further confirm the varicocele. The patient took the test results and asked why varicocele would cause a moist and sweaty scrotum. The veins of the testes and epididymis merge upward to form the internal spermatic vein, which enters the left renal vein on the left and the inferior vena cava on the right, and if the reflux is obstructed or the venous valves are dysfunctional, a trailing dilatation occurs, called varicocele. The prevalence of varicocele in adult men is 10-15%. Male sperm is produced by the testes in the scrotum, and the testes are temperature dependent. The body temperature is 37°C, and the appropriate temperature for sperm production is 34-35°C. If the temperature is too high, sperm production will be impaired. So the scrotum reaches this “low temperature” in a number of ways: the skin is thin and rich in sweat glands; the skin is wrinkled, increasing the surface area of the skin, which also increases the surface area for sweating and heat dissipation; the skin is rich in blood vessels, which can quickly take away excess heat from the scrotum; there is a thin layer of testicular muscle under the scrotal skin, which is very sensitive to changes in temperature. It relaxes when the temperature inside the scrotum rises, allowing the surface area of the scrotal skin to expand. When the surrounding environment or the internal temperature of the body rises slightly, the scrotal skin will “sweat” to dissipate heat, so under normal physiological conditions, the scrotal area is wetter than other parts of the body. When the varicocele, the blood vessels are tortuous and cannot carry away too much heat, plus the blood vessels are dilated, the testicular heat dissipation increases, which is also known as “sweating” increases, and the scrotal dampness will be more obvious. From the perspective of Chinese medicine, varicocele is a manifestation of the irregularity of the liver veins. If the blood vessels are not smooth and the qi and blood are not working, the scrotum and inner thighs will be swollen. Blood stasis and water stagnation turn into heat, and heat compels sweating, then we see vesicular sweating. The main treatment is to invigorate blood circulation, unblock qi and blood, resolve blood stasis and water stagnation, and clear heat and dry dampness. So I gave the patient a prescription for invigorating blood circulation and clearing heat and dampness, and asked the patient to take it regularly. The patient asked, “What should I pay attention to in my daily life? I said: you should develop the habit of washing the scrotum every day, keep the area clean and dry, do not wear tight pants, pay attention to a light diet and eat less spicy food; after sitting for a long time, you should exercise properly. In addition, scrotal dampness can not be classified as varicocele, if the scrotal dampness is accompanied by itching, pimples, etc., it may be suffering from scrotal eczema; scrotal dampness accompanied by frequent urination, urinary urgency, painful urination, lumbosacral pain, but also may be related to prostate disease, need regular medical treatment.