Abstract: To research the relation between the color of colored cotton/cotton blended yarn and colored cotton′s proportion,the color of 5 kinds of blended yarns with different colored cotton′s proportion were tested using computer color-measure and color-matching system,the results show that along with the change of colored cotton′s proportion the variety of hue of blended yarns is not very obvious,lightness is decreasing and chroma is increscent.Based on the value ofK/Sof 5 samples,by curve fitting using software Origin 6.1,it is drawn that the relation between colored cotton′s proportion and the value ofK/Sis linear relationship.Then,using regression analysis,the predicted range of blended yarns with any colored cotton′s proportion is drawn.