The oligosaccharide structures of total glycoproteins in suspension-cultured Arabidopsis thaliana MM2d cells are determined. The N-linked sugar chains released by hydrazinolysis were labeled with 2-aminopyridine, and analyzed by a combination of HPLC, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, and exoglucosidase digestion. The glycan structures determined were GlcNAcMan(3)FucXylGlcNAc(2) (8.5%), Man(3)FucXylGlcNAc(2) (70.0%), Man(3)XylGlcNAc(2) (13.7%), and GlcNAcMan(3)XylGlcNAc(2) (7.8%). All the glycan structures of glycoproteins from Arabidopsis MM2d cells used in this study contain typical plant bisecting either beta 1,2-xylose or alpha 1,3-fucose residues, showing that suspension-cultured MM2d cells have a glycosylation potential similar to that of tobacco BY2 suspension-cultured cells.