LigninsLignin in general have been extensively studied, while relation between source, isolation method and application is rarely described. In the present work, ligninLignin from different sources (wheat straw and beech woodBeech wood) and isolation methods (steam explosion, Organosolv) has been characterized regarding their application as a chemical resourceChemical resource and polymeric material. A range of analytical methods were applied including elemental analysis, FT-IR, 31P NMR, SEC, Py-GC-MS and HPLC to gain information about establish the purity, structure, molecular weight, thermal behavior and to determine carbohydrate residues according to the NREL protocol. TGA and DSC were used to study the thermal behavior of the isolated ligninsLignin and showed relatively low glass transition temperatures around 120 °C and decomposition temperatures between 340 and 380 °C. NREL analysis presented a carbohydrate-free ligninLignin fraction derived from beech woodBeech wood via Organosolv processOrganosolv process which has not been achieved to date. The finding of this work supports Organosolv as an efficient method to isolate pure ligninLignin fractions from beech woodBeech wood with practical value in industry, in particular for application in polyurethanes and phenolic resins.