a b s t r a c t Proteins play an important role in apatite formation in physiological environments. The effects of proteins partially result from changing apatite interfacial energy, and in turn, promoting or inhibiting apatite precipitation in physiological environment. The interfacial energies of hydroxyapatite (HA) crystallographic planes in aqueous solutions containing proteins and calcium and phosphate ions were calculated by molecular dynamics simulations. It provided reference interfacial energies for comparative study of protein effects that both acidic Human serum albumin and basic Lysozyme reduces the interfacial energy of H