The catechin and proanthocyanidin compositions of the leaves and bark ofZiziphus jujuba have been studied over the vegetation periods. This has led to the isolation of 16 compounds, including 8 monomeric catechins — (−)-epiafzelechin, (−)-epicatechin, (−)-epigallocatechin, (−)-epicatechin gallate, (−)-epigal-locatechin gallate, (+)-catechin, (+)-catechin gallate, and (+)-gallocatechin; 4 dimeric proanthocyanidins — (−)-epiafzelechin-(4β-8)-(−)-epicatechin, proanthocyanidin B-2, (−)-epicatechin-(4β-8)-(−)-epigallocatechin, and (−)-epiafzelechin-(4β-8)-(−)-epigallocatechin; and 4 oligomeric proanthocyanidins consisting of epiafzelechin, epigallocatechin, catechin, and epicatechin with different degrees of polymerization. Their structures have been established by a study of PMR and13C NMR spectra and the products of chemical transformation.