A stent delivery system provided by the present application comprises: a radiopaque tip located at the distal end of the stent delivery system； a beads component comprising at least one expandable part； a funnel component comprising a distal flare structure and a proximal collapsed end, wherein the cross-section of the flare structure gradually increases from its minimum diameter to its maximum diameter along the proximal-to-distal direction； and a core wire located at the proximal end of the stent delivery system； and wherein the distal end of the beads component is fixed on the radiopaque tip and the proximal end of the beads component is fixed on the core wire； wherein the funnel component is coupled with the beads component and the core wire, and is fixed on the core wire through the collapsed end. The present application also provides a flow diversion device and an assembly method of the flow diversion device.
