The phenomenon of flashing light when turning the eyeball may be due to physiological factors or pathological factors, such as vitreous blood accumulation and retinal tear. 1. Physiological factors: as the body ages, the vitreous body will liquefy, degenerate and detach, which will lead to the phenomenon of flashing light when turning the eyeballs, which usually does not affect the vision and does not need to be treated. 2. Pathological factors (1) Vitreous hemorrhage: due to the rupture of small retinal blood vessels or diabetic retinopathy and other factors causing hemorrhage, its blood or exudate into the vitreous, which will appear red or gray-white flakes or clusters of turbidity, when turning the eyeballs there will be flashes of light. (2) retinal fissure: the vitreous body pulls the retina to form a fissure or retinal degeneration and atrophy to form a hole, there are no obvious symptoms in the early stage, but with the aggravation of vitreous liquefaction, there can be a fixed position in front of the eyes to appear the phenomenon of continuous flash feeling, so turn the eyeball there will be a flash of phenomenon. Flying mosquito turning eyeballs have flash in the exclusion of physiological factors, the need to consult a doctor in a timely manner, in accordance with the doctor’s instructions for treatment.