The utility model relates to a novel high cavity precise bottle cap mould adopting an HALF block structure, which comprises an HALF block (3), a mould cavity (5), a large sliding block A (1), a large sliding block B (2) and wedge blocks (4), wherein a positioning bore-hole and a positioning straight hole are formed in the upper end face and the lower end face of the HALF block (3) respectively; bevels are arranged on the two sides of the HALF block (3); the mould cavity (5) is mounted inside the positioning bore-hole in a matching manner; the wedge blocks (4) are tightly matched with the bevels; a pushing ring (6) is mounted inside the positioning straight hole in a matching manner; the large sliding block A (1) and the large sliding block B (2) are arranged at the lower part of the HALF block (3); a cooling water core (8) is connected with a threaded mold core (7) in a matching manner; a pushing pipe (9) is mounted inside the cooling water core (8) in a sleeving manner; and an inner mold core (10) is mounted inside the pushing pipe (9). The novel high cavity precise bottle cap mould has the advantages that the boundary dimension is small, the manufacturing cost of the mould is low, the matching precision of the mould is high, the operation is stable, the processing precision can be guaranteed easily and the service life is long.