Because of recent advance in supercomputer it is getting possible to perform molecular dynamics (MD) simulations of biomolecules such as protein, DNA, and RNA after building up accurate molecular models based on quantum mechanics. Using high-level quantum mechanical theory we are developing more accurate unified force field than traditional ones. Using nonequilibrium Jarzynski identity we developed massively parallel computational method of binding free energy (MPCAFEE), which made it possible to quantitatively compare the calculated binding free energies with experimental binding constants commonly measured in the drug development. Recently we have succeeded to improve the accuracy of DNA and lipid force field in consistent way with the protein force field. We will continue the research to make concrete physical basis for the life science.