Diabetes and cataracts are both diseases of the elderly and often occur in the same person. Moreover, high blood sugar is also an important factor that promotes the occurrence and development of cataracts, so cataracts in diabetic patients occur earlier and progress faster than the general population. As we all know, when cataracts develop to a certain level, they need to be treated with surgery. So, is there something special to note about cataract surgery for diabetic patients? Before surgery: Check the fundus in as much detail as possible. The real killer that threatens the vision of diabetic patients is diabetic retinopathy, not cataract. Cataract surgery can restore vision, but the loss of vision due to retinopathy is irreversible. Therefore, before cataract surgery, it is important to know whether the retina has lesions or not? What is the extent of the lesion? If laser treatment is needed and the cataract has not completely affected the laser treatment, the fundus lesion must be treated first, and as far as possible, retinal laser treatment must be adequately performed first before cataract surgery. Blood sugar must be well controlled before surgery, as much as possible below 8 mmol/l, otherwise the wound will not heal easily after surgery, and it will also easily lead to eye infection with serious consequences. After surgery: After surgery, the inflammatory reaction in the eye of diabetic patients is heavier and lasts longer than that of the general population. Therefore, hormonal eye drops must be ordered as prescribed by the doctor and must not be reduced or stopped on their own. We have seen many patients who stopped taking the drops on their own for various reasons, resulting in severe reactions and vision loss. It is also important to check the fundus as soon as possible after surgery, especially for patients with heavy preoperative cataracts and difficulty seeing the fundus, and to check the fundus in detail within 1 week after surgery. Patients who already have retinal hemorrhage and exudation should have fundus angiography as soon as possible, and if necessary, laser treatment must be done as soon as possible. Because, if there is already retinopathy before surgery, after cataract surgery, it will develop and deteriorate quickly, and again vision loss will be irreversible. In conclusion, for diabetes + cataract, it is important to focus on fundus lesions and control them first before cataract surgery if possible. It is also important to be highly alert to changes in the fundus after surgery.