Abstract: According to the Chinese dictionary word segmentation efficiency that based on the Double-Character-Hash-Index（DCHI） mechanism exceeds clearly based on the First-Character-Hash-Index（FCHI） mechanism，this paper lucubrates to the Chinese word-building characteristic and provides a new segmentation dictionary mechanism named Three-Character-Hash-Indexing（TCHI） mechanism，which exploits character coding index sufficiently.The results show that the TCHI dictionary mechanism can improve speed and achieve more efficiency than FCHI，DCHI and four；character-hash-index in Chinese dictionary word segmentation mechanism.