With the progress of science and technology, the continuous improvement of surgical equipment and the continuous development of surgical instruments, the timing of cataract surgery has also changed, as follows: 1. Cataract grows into full white: the earliest cataract can be operated only when it has matured, that is, when the cataract all grows into full white and the vision is reduced to manual or index; 2. Vision is reduced to less than 0.5: nowadays, the widely used Ultrasonic cataract surgery, in textbook terms, means that the vision of the naked eye is reduced to less than 0.5, and surgery can be considered; 3. Affecting daily life: However, due to the increasing demand for visual function, mild or moderate cataracts, although they do not affect the vision of the naked eye to less than 0.5, but affect daily life, can also be considered for surgery. Therefore, the timing of cataract surgery should not be generalized, but should be considered in light of individual circumstances, as well as the degree of cataract development and its impact on life. Cataract surgery can be considered once the development of cataracts has affected daily life.