Abstract: In order to study the fiber radial distribution of blended yarn in complete condensing spinning, polyester/cotton blended yarn was spun in ring spinning, Lattice apron compact spinning and Complete condensing spinning systems respectively. The kinds of blended yarn sample are cut by chip cutter. By using MOTTC B1 microscope and Hamilton Migration Index method, the migration trend and radial distribution of fibers in the polyester/cotton blended yarns were studied. It is shown that the polyester is prioritized to transfer inside. Comparing with ring spinning, the migration index of fibers in the blended yarns spun by Lattice apron compact spinning systems is smaller. Comparing with Lattice apron compact spinning systems, radial distribution of fibers in the blended yarns spun by complete condensing spinning system is more random.