The advantage of multifocal IOL is that it can be adjusted at distance and near, i.e. it produces two focal points at distance and near, realizing the function of natural human crystals, which allows free adjustment of the focal point when looking at something. Multifocal IOL is a new type of IOL, available in diffractive and refractive types, which can help cataract patients to restore their vision at both near and far; compared with monofocal IOL, the near vision of multifocal IOL is better than that of monofocal, while the distance vision is the same as that of monofocal. Multifocal IOL can satisfy the near vision of elderly people who play with cell phones and computers in daily life, and it can also satisfy the far vision of elderly people who drive and other complicated situations. Multifocal crystal refractive type belongs to biconvex lens, which has a wide range of field of vision, but it is overly dependent on the size of human pupil, and there will be a decline in the quality of imaging after a long period of time; diffractive type redistributes the light, which has a good quality of imaging, but it will produce the phenomena of glare and wheel glare for a long period of time. If cataract elderly patients want to use multifocal IOL implantation, it is recommended to go to regular hospitals for treatment.