Abstract: Neutron scattering is a technique that helps to unravel the mysteries of the microscopic world by studying the changes in the momentum and energy of incident neutrons after collision with nuclei. Because the scattering cross section of a hydrogen atom is much larger than that of other atoms, neutron scattering has excellent applications in studying the structure and dynamics of biological macromolecules containing a large number of hydrogen atoms. In this paper, we introduce the principles and recent progress of primary neutron scattering techniques that can be applied in the field of biological science, including neutron crystallography and variable contrast small angle neutron scattering for structural biology, quasi-elastic neutron scattering, and neutron spin echo techniques for macromolecular dynamics studies. Finally, future challenges for discovering new physics phenomena in the biological sciences by neutron scattering are discussed.