Abstract: This study explores the interaction of bioactive AED tripeptide molecules with new lysine-based dendrimer KHR containing spacers consisting of two different amino acid residues (histidine-arginine, HR). Previous research has examined second-generation lysine dendrimers containing double charged lysine-lysine and arginine-arginine spacers as well as double hydrophobic alanine-alanine and leucine-leucine, and double pH-sensitive histidine-histidine spacers. Interactions of some of these dendrimers with several bioactive peptide, for example, AEDG were studied also. In this work, similar molecular dynamics simulations were conducted to study the complexation of 16 AED molecules with KHR dendrimer at two pH values: (a) pH > 7 with uncharged histidines and (b) pH < 5 with fully protonated histidines. Results indicate that dendrimer at both pH make complex with AED but dendrimer at smaller pH can accommodate more AED molecules.