Complex glycosylation patterns containing multiantennary N-glycans are typically found in mature glycoproteins. However, the structural characterization of these glycans is rather challenging. Usually, standard NMR and X-ray diffraction techniques fail to provide specific answers on the structure and molecular recognition features due to intrinsic attributes of the glycan. As a promising approach, carbohydrates conjugated to lanthanide binding tags have revealed high potential toward this aim. This methodology has first been applied to the study of small oligosaccharides (di-, tri- and tetrasaccharides). Proceeding from this experimental basis, we have extended this concept to the level of high degree branching and long chain N-glycans. In addition, the molecular recognition properties of these complex glycans were characterized in detailed thanks to the unprecedented resolution obtained in the spectra.