In order to explore the difference of tannin content and structure of dry red wine in different vintages and its relationship with astringency intensity， the total tannin content， free flavan-3-ol monomers content and condensed tannin structure components of Cabernet Sauvignon and Cabernet Gernischt dry red wines from Inner Mongolia in different vintages were determined， and the astringency intensity of wines was evaluated by sensory tasting. The results showed that the total tannin content and total flavan-3-ol monomers content of new wines were higher than those of aged wines. The catechin and epicatechin gallate content of new wines were higher， while the epigallocatechin and gallocatechin content of aged wines were higher. Among the structural characteristics of condensed tannins， the proportion of procyanidins was higher in new wines， while the proportion of prodelphinidins was higher in the aged wined. Furthermore， the tannin structure of wines aged 8-9 years tended to be stable. Principal component analysis between astringency intensity and wine components showed that total tannin， the average degree of polymerization， epigallocatechin gallate monomer， epicatechin and epicatechin gallate in the terminial unit and galloylation degree had a more significant influence on astringency intensity. In contrast， total acid， pH value， alcohol， total phenols， anthocyanin and free monomers had less influence.