Red dots under the eyes are usually caused by the following: first, due to subconjunctival hemorrhage, which usually occurs when small blood vessels on the surface of the white eyeball rupture due to accidental eye bruising, eye rubbing, violent coughing, sneezing, constipation, etc. Small patches of hemorrhage occur. Second, it is caused by subcutaneous bruising of the eyelid, which occurs on the skin surface below the eye. Rubbing the eye during painful crying makes it most likely to occur due to the mechanical stimulation of the eyelid skin tissue by rubbing the eye, causing small blood vessels to be pulled off thus forming a punctate hemorrhage. Third, spider nevus of the eyelid skin is a special type of subcutaneous vasodilatation that usually occurs in patients with abnormal liver function. Due to disorders of estrogen metabolism in the body caused by liver disease, skin blood vessels become abnormally dilated, resulting in the formation of small red dots that are most likely to appear on the skin under the eyes.