Two new ellagitannin monomers, heterophylliins A (12) and E (13), and three dimers, heterophylliins B (17), C (18) and D (19), were isolated from leaf extract of Corylus heterophylla (Betulaceae), and their structures were elucidated based on spectral and chemical evidence. Seven known tannins, 1, 2, 3, 6-tetra-O-galloyl-β-D-glucose, tellimagrandin II, casuarictin, casuarinin, rugosin C, rugosin F, and degalloylrugosin F, were also isolated.