When the content of magnetic fiber increases, the twist of the yarn will also increase; and when the content of magnetic fiber does not change, the twist of the yarn will first increase and then decrease with the increase of bamboo pulp fiber content. This trend is determined by the performance of the polypropylene staple fiber itself: although the magnetic fiber is smoother than cotton fiber and bamboo pulp fiber, it has a longer length and is easy to gather fiber twists to reduce fiber transfer in and out of the yarn. Under the same spinning conditions It is easier to get a higher twist under the lower part; it is different from the shape of cotton fiber and bamboo pulp fiber, so the hairiness morphology produced will also be different. When different types of hairiness are entangled together, the twist can be tighter. The twist will be relatively high when the fiber content of bamboo pulp is close.