In this paper, various variables of the rotor spinning system were optimized to produce cotton yarn from ginning waste with the lowest hairiness level. Using the Taguchi method, the effect of rotor parameters (diameter and speed), the navel type, the opening roller speed and yarn linear density on the level of yarn hairiness was investigated. The raw materials used in this investigation were cotton fibers and cotton waste collected from ginning machines. Yarns were produced from three different waste proportions (65%, 50% & 35%). The present study of the influence of ginning waste on the hairiness of open-end yarn indicated that for all the yarns produced with different waste proportions, the rotor diameter and navel type are the most influential factors. Moreover the results show that the opening roller speed does not seem to exert a substantial influence on the hairiness of spun yarns. For the rotor yarns optimum spinning conditions were determined in order to obtain the lowest hairiness level.