Abstract: Five kinds of polypropylene filament/aramid wrapped yarns with different twist were produced successfully with the parallel spinning method by adjusting winding speed and spindle speed of ON-SC1000 fancy twisting machine. Seven indexes were Selected to analyze the comprehensive performance of the wrapped yarn, including the breaking elongation CV、the breaking strength CV, slug, knot, snicks ,evenness, abrasion performance which were defined as X1、X2、X3、X4、X5、X6、X7 in turn. It was calculated that the five kinds of wrapping yarn got the comprehensive score of 0.067, -0.818, -0.751, -0.818, 1.476 with the principal component analysis method. Experiments demonstrated that the rank of yarns with different twist is 320T/m、250T/m、300T/m、200T/m、350T/m successively; When the twist rang from 250 T/m to 320T/m，the wrapped Yarns get excellent comprehensive performance which is benefit to give full play to the excellent characteristics of the two kinds of fiber. The analysis results provide much practical guidance for designing the twist of Polypropylene filament /aramid wrapped yarn correctly.

Key words: ploypropylene filament, aramid, wrapped yarn, twist, yarn prality, principal component analysis