There is no direct correlation between cataract surgery and mosquito flying, and cataract surgery does not aggravate the symptoms of mosquito flying. Flying mosquitoes are observed after cataract surgery mainly because: First, patients who undergo cataract surgery are middle-aged and elderly, and middle-aged and elderly people themselves will have vitreous clouding and flying mosquitoes. Secondly, patients with cataracts have relatively poor vision before surgery, which is due to the blockage of cataracts. After cataract surgery, the original cloudy lens is replaced with a very high transparency IOL, which will make the patient feel that the clarity of vision has improved significantly, and the comparison between preoperative and postoperative vision will be obvious. After the postoperative clouding of the lens is removed, it appears that the symptoms of vitreous opacification are more clearly observed. Cataracts will feel more obvious after cataract surgery, discomfort because the symptoms are aggravated, but because after the replacement of the lens, the cataract that has a greater impact on vision is removed, the original vitreous clouding that has little impact on vision, becomes a relatively obvious symptom, the essence is not the symptoms themselves have changed.