Abstract: An occluder has a first disk-shaped structure with a grid, wherein the first disk-shaped structure is woven from at least two groups of braided wires, and the two groups of braided wires are crossed to form multiple rings of crossing points. A blocking membrane is also arranged in the disk-shaped structure, with an edge of the blocking membrane connected to the outermost ring of crossing points of the multiple rings of crossing points through a sewing wire, and the number of crossing points in the outermost ring of crossing points sewn with the blocking membrane is smaller than the number of all the crossing points in the outermost ring of the crossing points. The occluder can reduce the possibility of the phenomenon where the edge of the blocking membrane cannot abut against a disk face edge of the occluder, thereby improving the occlusion effect of the occluder.