Purpose: To report a case of late opacification of a hydrophilic acrylic monofocal intraocular lens (IOL) with a hydrophobic surface (CT SPHERIS ® 204) after a second vitrectomy in a patient with proliferative diabetic retinopathy. Case summary: A 50-year-old male with diabetes presented with decreased visual acuity in the right eye. He had undergone phacoemulsification and IOL (CT SPHERIS ® 204) implantation, vitrectomy, endolaser photocoagulation, and intravitreal bevacizumab (Avastin ®) injection due to vitreous hemorrhage in the right eye about 43 months prior. Four months after the surgery, presenting with recurrent vitreous hemorrhage and neovascularization of the angle, he underwent partial vitrectomy and intravitreal and intracameral bevacizumab (Avastin ® ) injection. The best-corrected visual acuity was 0.1 in the right eye when he presented with decreased visual acuity. Slit lamp examination of the right eye showed diffuse whitish granular opacity on the surface of the IOL. The IOL was explanted, together with the capsular bag, and examined using scanning electron microscopy and energy-dispersive X-ray spectroscopy. Conclusions: This case is the first to report late opacification of a hydrophilic, acrylic monofocal IOL with a hydrophobic surface, the CT SPHERIS ® 204. It is necessary to be cautious in using this type of lens in patients with diabetic retinopathy.