Four gallotannins: 1,2,3-tri-O-galloyl-b-glucose; 1,2,3,6-tetra-O-galloyl-b-D-glucose; 1,2,3,4,6-penta-O-galloyl-b-D-glucose and 1,2,3,4,6-penta-O-galloyl-a-D-glucose, together with gallic acid and methoxy gallic acid have been isolated from the seeds of Quercus robur and their stuctures were elucidated on the basis of chemical and spectral evidence.