Purpose To evaluate soluble fibronectin, vitronectin, and collagen type IV adhesion to poly(methyl methacrylate) (PMMA), fluorine-surface-modified PMMA, silicone, hydrophobic and hydrophilic acrylate, and hydrogel intraocular lenses (IOLs) and determine whether hydrophobic and hydrophilic acrylate materials have different fibronectin-adhesion properties. Setting Department of Medical Biochemistry, University of Oulu, Oulu, Finland. Methods One hundred fifty IOLs were incubated for 1 week at 37°C with radioactive-iodine-labeled soluble fibronectin, vitronectin, or collagen type IV. Fifty IOLs were analyzed for each protein, 5 from each of 10 different IOL models (PMMA, Alcon MC60BM; fluorine-surface-modified PMMA, Chiron Fluorilens Centra-55F; silicone, Allergan Medical Optics SI-40NB and Pharmacia & Upjohn CeeOn® 911A; hydrophobic soft acrylate, Alcon AcrySof® MA60BM and SA30AL and AMO® Sensar®; hydrophilic soft acrylate, Ioltech Stabibag and Bausch & Lomb BL27; and hydrogel, Bausch & Lomb Hydroview®). The amount of adherent protein was measured with a gamma counter at 1 and 7 days and expressed as counts per minute. Results At 1 week, significantly more fibronectin was bound to the hydrophobic acrylate IOLs than to the 2-hydroxyethyl methacrylate (HEMA) containing hydrophilic acrylate IOLs ( P < .05 to .0001). Significantly more vitronectin was bound to the 2 silicone IOLs than to any other IOL ( P < .01 to .0001) at 7 days. Collagen type IV adhered best to the hydrophilic acrylate IOLs, which were significantly different ( P < .01 to .0001) than the other IOLs at 1 and 7 days. Conclusions Each IOL material had a different affinity to each protein. Significant binding to 1 protein does not indicate that the IOL will bind significantly to all proteins; instead, each protein should be studied separately. Fibronectin bound significantly better to hydrophobic acrylate IOLs than to hydrophilic acrylate IOLs, suggesting that the HEMA-containing IOLs should be classified with the hydrogel IOL group.