Abstract: Based on the double wefts all-coloring structure, color variation characteristics of jacquard fabric juxtaposition color mixture can be calculated through both color compound mode and proportion of color wefts. Sample test weaving carried out by red weft compound with other basic color wefts (red & green, red & blue, red & yellow), inputting computer with scanistor, then imitating the fabric sample on computer, obtaining simulated image, calculating the L*, a* and b* chroma value of imitated fabric in computer average color method of calculation, comparing L* value and calculating chromatism with the former. As the results showing: brightness changing of all-coloring double weft jacquard fabric with juxtaposition color mixture has distinct regularity. Although there is certain chromatism between fabric sample and imitated fabric, practical color model or color table can be set up, based on color mixture characteristics of double-weft jacquard fabric, for guiding designing on this kind of fabric.