Recent research suggests that the biocompatibility of an implant is to a large extent determined by selective adsorption of proteins from surrounding body fluids. Protein adsorption from human plasma onto two bioactive glass-ceramics (RKKP and AP40) which differ in La and Ta content, was studied by means of chromatography and two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). The quantitative analysis showed that the glass-ceramics have good protein binding capacities indicating multilayer formation. A correlation between chemical composition and the amount of adsorbed proteins was observed. The presence of La and Ta decreased the protein adsorption, so AP40 bound significantly more protein per surface unit then did RKKP. Preferential adsorption of apolipoprotein J, fibrinogen and fibronectin was observed.