Studies have suggested that the adsorption of fibrinogen onto a biomaterial’s surface plays an important role in determining a material’s blood compatibility. In this study, fibrinogen adsorption from various dilutions of human blood plasma was measured on various radio frequency glow discharge (RFGD) modified surfaces. In addition, the relative binding strength of adsorbed fibrinogen on these surfaces was assessed by subsequent sodium dodecyl sulfate (SDS) elution. More fibrinogen was adsorbed on the hydrophilic surfaces modified by an ammonia plasma, a sulfur dioxide plasma, and an ammonia plasma with propane sultone post treatment than on the untreated polyethylene control. These three hydrophilic surfaces also exhibited higher fibrinogen retention values than the untreated polyethylene control did. The high in vitro fibrinogen adsorption results observed on these hydrophilic surfaces are closely parallel to those obtained previously in ex vivo canine shunt experiments. Transient fibrinogen adsorption, also known as the "Vroman Effect," was not observed on the surfaces modified by the ammonia plasma and the ammonia plasma with propane sultone post treatment. In contrast, maxima in fibrinogen adsorption were noticed on the surface modified by the sulfur dioxide plasma. Despite the variations in surface chemistry, similar fibrinogen adsorption and SDS elution results were noticed on a Silastic control surface and surfaces modified by various plasma polymerized siloxanes.