In this paper; the properties o yams which were produced by using a modified ring spinning system (ProSPIN (R)) and conventional ring spinning system were comparatively investigated. The modified spinning system which was used in yarn production has basically the characteristic of compact spinning system and is at present used especially in the production of mid-count yarns. In this study, conventional ring yarns and equivalent modified ring spun yarns were produced with different yarn counts and twists using 100% carded cotton raw material. Tests were conducted to determine the tensile, unevenness, imperfection and hairiness properties of the yarns. It was found that the modified ring spun yams showed considerable positive differences in some yarn properties compared with conventional ring yarns. The diffrrences in tenacity values were more evident especially in yams with lower twist coefficients, while differences in hairiness values were more so in finer yarns. Also the unification of two separate and compacted fibre strands during yarn formation ensures better values for both mass irregularity and IPI because of the doubling effect.