Abstract: As a result of different spinning types,different kinds of yarns have different structures and performance.Open-end rotor spun composite yarn was produced on a modified rotor spinning machine.And sirofil yarn was produced on a modified ring spinning machine under the same spinning conditions and according to the same standard as open-end rotor spun composite yarn.The longitudinal views,abrasion resistance,hairiness and breaking strength of the two kinds of composite yarns were tested and analyzed.Through comparative study it revealed that open-end rotor spun composite yarn has a smoother surface,less hairiness,less pilling,and higher abrasion resistance,but its strength is slightly lower than that of sirofil yarn.