Molecular dynamics (MD) simulation is a powerful tool to reveal molecular interactions and has also been extensively utilized to study the interactions between Ca 2+ and membranes. However, previous studies showed that the Ca 2+ models used in classical nonpolarizable force ields were often inaccurate in describing the Ca 2+ -biomolecule interactions. Recently, we developed a multisite Ca 2+ model, which signiicantly improved the calculation accuracy for the Ca 2+ -protein interaction. Considering that the dielectric constant of membranes is close to proteins, we expect that the new model would generate more reliable simulation results in the study of Ca 2+ -membrane interactions as well.