Cotton assorting method and device of yarn, and yarn

The invention discloses a cotton assorting method and device of a yarn, and the yarn. The cotton assorting method of the yarn comprises the following steps: according to the first predetermined quality standard, selecting first cotton accounting for 26.8% of the total and second cotton accounting for 73.2% of the total for cotton assorting, wherein the quality standard of the first cotton is higher than that of the second cotton; according to the second predetermined quality standard, in the second cotton, selecting first-class cotton accounting for 20.1% of the total and second-class cotton accounting for 53.1% of the total, wherein the quality standard of the first-class cotton is higher than that of the second-class cotton. With the technical scheme, the good and the bad are matched, and the effect of different batches of same cotton on quality can be reduced.