Abstract: Virus infections remain major threats to human health worldwide. Viruses are intracellular parasites, and must enter host cells and deliver their genetic material to initiate infection. Virus entry is a highly complex process that may involve hundreds of trans-membrane and peripheral membrane proteins. This highly complex process is dictated by various events, such as virus motion, membrane deformation and merging as well as molecular scale protein-protein, protein- lipid interactions and drastic protein conformational changes, occurring at multiple stages and at multiple length and time scales. The question of how these biochemical and biomechanical events work together culminating in productive entry is not well understood but fundamentally important for development of vaccine candidates and identification of new targets for inhibitor design. Modeling and simulations of virus entry at different scales can provide mechanistic insights into this complex process. In this talk, we will present our recent simulation research on membrane deformation and protein conformational changes for virus entry. A mesoscale stochanstic membrane model has been implemented to investigate the membrane deformations during the entry process. We will also discuss our development of the coase-grained force field to capture the protein conforamtional changes, and the on-going work of machaine-learning facilitated sampling of protein structures.