An atrial appendage occluder capable of entering a half-released state by means of pushing a head-end fiber comprises: an occlude body (1); a head-end control fiber (2); and a tail-end control fiber (3). A head end of the occluder body (1) is connected to one end of the head-end control fiber (2) by means of a head-end threaded bushing (4). A tail end of the occluder body (1) is connected to one end of the tail-end control fiber (3) by means of a tail-end threaded bushing (5). The tail-end control fiber (3) is in the form of a hollow column. The other end of the head-end control fiber (2) sequentially passes through the tail-end threaded bushing (5) and the tail-end control fiber (3). The occluder body (1) is in a woven-net support structure, and has a shape preconfigured to match the structure of an atrial appendage after the occluder body (1) has been fully released. The occluder body (1) is in the form of a strip and disposed in an outer sheath (6) before being released. The occluder body (1) is in a half-release state after being pushed out of the outer sheath (6). The diameter of the occluder body (1) is changed by pushing or pulling the head-end control fiber (2, 3). The atrial appendage occluder can adjust its location in the atrial appendage, such that the occluder can be released precisely in a preset location.