Certified　Reference　Materials　(CRMs)　with　high　accuracy　and　metrological　traceability　play　an　important　role　in　calibrating　equipment　and　validating　analytical　methods.　L-　fucose　is　a　ubiquitous　natural　a　six-carbon　sugar　that　has　many　promising　biological　physiological　functions.　It　can　be　used　in　medicine,　food,　healthcare　products,　cosmetics,　and　other　fields.　To　accurately　determine　the　content　of　L-fucose　in　various　samples,　a　reliable　CRM　needs　to　be　developed.　In　this　study,　an　new　L-fucose　purity　CRM　was　developed　based　on　the　ISO　principle.　The　study　included　structural　analysis,　characterization,　homogeneity　test,　stability　evaluation,　and　uncertainties　estimation.　The　mass　balance　(MB)　and　quantitative　proton　nuclear　magnetic　resonance　(q　1H　NMR)　methods　were　used　for　characterizing　the　CRM.　Using　the　MB　method,　main　component,　moisture,　and　nonvolatile　and　volatile　impurities　were　measured.　the　PC　of　CRM　was　identified　by　performing　high-performance　liquid　chromatography　coupled　with　ultraviolet　detection　(HPLC-UV)　using　the　pre-column　derivatization　procedure.　L-fucose　purity　CRM　was　found　to　be　stable　for　18　months　under　ambient　temperature　conditions,　whereas,　30　days　at　50　°C.　It　was　adequately　homogeneous.　At　a　95　%　confidence　level,　its　certified　value　was　99.5　±　1.2　%　(k　=　2).　©　2025　Elsevier　B.V.