The 26‐residue peptide melittin present in bee venom has been shown to bind calmodulin tightly. In this study we synthesized the following series of deletion peptides of melittin by the solid‐phase method: Mel12, Mel13, Mel 14, Mel 15, Mel15F. The results of this study show that the deletion peptides Mel 14 and Mel 15 have almost the same binding activity as the intact native peptide. Each deletion peptide forms a 1:1 complex with calmodulin according to electrophoresis analysis. When the tryptophanyl residue of Mel15 was replaced by the phenylalaninyl residue, the dissociation constant of the peptide—calmodulin complex increased. This shows the importance of the tryptophanyl residue for binding to calmo