The invention belongs to the field of micro-bore diameter multichannel pipe preparation and provides a supercharged multichannel pipe divergent die composite die core. The supercharged multichannel pipe divergent die composite die core comprises a die core, a lower die and a lower die supporting plate, wherein a lower die through hole is formed n the center of the lower die; the outer contour of the lower die supporting plate is identical with the shape and the dimension of the lower die through hole; the thickness of the lower die supporting plate is smaller than the thickness of the lower die; the lower die supporting plate is located inside the lower die through hole; a plurality of upper die core needles are mounted in the bottom of the die core; a plurality of lower die core needles which are matched with the upper die core needles are mounted on the top of the lower die supporting plate; two horizontal sliding grooves are symmetrically formed in the inner wall of the lower die; springs and boss sliding blocks which are connected with the springs are horizontally fixed in the sliding grooves; the boss sliding blocks comprise bosses and substrates; supporting grooves which are matched with the front ends of the bosses are formed in the lower supporting plate; the lower supporting plate is supported inside the lower die through hole by the bosses; and the front ends of the bosses shrink into the sliding grooves and can be fixed in the sliding grooves. According to the supercharged multichannel pipe divergent die composite die core, the extrusion force, the mold filling efficiency and the mold filling capacity during extrusion forming are improved, so that the forming quality of a product is improved.