Black spots after cataract surgery may be caused by posterior cataract, vitreous clouding and secondary glaucoma. 1. Posterior cataract: after cataract surgery, cell proliferation occurs in the posterior capsule membrane, which makes it turbid again, and it can be manifested as postoperative black spots, which usually need laser treatment. 2. Vitreous clouding: the occurrence of this disease is related to vitreous liquefaction, vitreous detachment, vitreous hemorrhage, surgical trauma and other reasons. Patients mainly show that there are black shadows floating in front of their eyes, vision loss, and so on. 3. Secondary glaucoma: This disease mainly refers to the abnormal elevation of intraocular pressure, resulting in progressive damage to the optic nerve, which may be due to the interference with the normal atrial aqueous humor circulation after cataract surgery, resulting in elevated intraocular pressure, and then there will be a postoperative black spots in the eyes. Symptoms such as headache, eye swelling and blurred vision may also occur. Patients with dark spots in the eyes after cataract surgery need to go to the hospital in a timely manner to improve the examination in order to clarify the exact cause.