Nuclear magnetic resonance spectroscopy has been one of the most important analytical techniques to analyze biomass materials and their transformation products. 1H, 13C, 15N, and 31P NMR techniques have been used to analyze carbohydrates, proteins, lipids, and polycondensed compounds in raw and processed biomass, from plants, animals, fungi, algae, and other living beings. NMR has been used in qualitative and quantitative analyses of biomass materials, determination of the chemical composition, and structure and dynamics of monomers, oligomers, and polymeric materials. One of the major NMR advantages is its nondestructive nature that maintains sample integrity, and the analyzed samples can be analyzed by other methods. This chapter provides basic information about NMR measurements and spectroscopic parameters, analysis in solid state, liquid state, and in heterogeneous samples.