The interaction of calreticulin with amyloid beta (Aβ) was investigated using solid phase and solution binding assays. Calreticulin bound Aβ 1-42 in a time and concentration dependent fashion. The binding was optimal at pH 5 and was stimulated by Ca2+ and inhibited by Zn2+ at pH 7. Interaction took place through the hydrophobic C-terminus of Aβ 1- 42 and the polypeptide binding site of calreticulin. The results are discussed in the light of a reported role of calreticulin as a cell surface scavenger receptor.