Objective: To investigate the effect of intraocular lens (IOL) pre-suspension in thetreatment of severe lens subluxation. Methods: Retrospective case study. From December 2018 to July 2022, 8 eyes of 8 patients with severe lens subluxation greater than 180 degrees admitted to our hospital were selected. During surgery, the IOL should avoid the subluxated lens and be pre-suspended in the vitreous cavity, and then the lens is lifted and placed above the IOL. If necessary, the iris hook can be used to stabilize the lens to ensure the safe completion of phacoemulsification. Results: There were 8 patients with severe subluxation of lens. Among them, the hardness of 3 patients' lens nucleus ranged from N1 to N3. In these 3 patients, we used the IOL pre-suspension alone to stabilize the subluxated lens, and phacoemulsification in these 3 patients was successfully completed. Three patients had N4 and 2 patients had N5, of which 4 patients underwent phacoemulsification safely with the assistance of iris hook. In another patient with N5, the lens fell into the vitreous cavity during surgery (the suspension ligament rapture greater than 270 degrees) when it was lifted and placed on the IOL which was crushed by the vitreous cavity ultrasound. After surgery, the IOL was centered in all 8 patients, visual acuity was improved to varying degrees, intraocular pressure was normal, and no serious complications were observed. Conclusions: In severe lens subluxation surgery, IOL presuspension in soft nuclei of N2 to N3 can stabilize the lens well and ensure the safety of phacoemulsification. For hard nuclei N4 to N5, IOL presuspension can be used as an auxiliary method in combination with iris hook to stabilize the lens and ensure the safety of phacoemulsification.