This study surveys the warp and weft tension differences among 3 types of rapier looms and analyses the mechanical properties of worsted fabrics for garment with relation of these looms characteristics using KES-FB system. Raper is divided by two parts. In the 1st paper, the worsted fabric is woven as 5 harness satin weave using 1/40 Nm sirofil worsted warp yam and 1/30 Nm worsted weft yam by rapier looms such as FAST-R, THEMA-11-E and PICANOL-GTX respectively. The weavability is also analysed by measuring warp tension variation according to the warp position and weft tension of 3 kinds of looms. The relationship between shed amount and the warp tension is surveyed, and the relationship between end breaks and warp and weft tensions is also discussed.