Dense black dots in the sky are often considered to be caused by vitreous clouding. Vitreous clouding can also be called flying mosquito, mostly belongs to the normal physiological conditions, the main clinical manifestations are described as floating black spots in front of the eyes, in the look at the sky or the white background of things will be more obvious. Aedes aegypti is more common in people with high myopia, and vitreous degeneration and liquefaction with aging is also an important cause of aedes aegypti, which generally does not require special treatment. Physiologic vitreous clouding that affects vision can be treated with medications such as lecithin complex iodine under the direction of a doctor to improve symptoms. If the clouding is sudden or the black shadow in front of the eyes suddenly aggravated, it is necessary to consult a doctor to rule out retinal detachment, diabetic retinopathy fundus hemorrhage and other fundus diseases. Dense black dots in the sky are mostly considered to be due to physiological reasons, if it affects normal vision, it is recommended to consult a doctor as soon as possible.