The invention discloses a dust-free pure black processing method for polyester-cotton blend/cotton knitted shell fabrics, and aims to improve yarn structures, a dyeing process and dyeing technology and provides an overall solution to solve the problems that the fibers are damaged to a certain extent, and the down dust falls off and cannot be completely removed by general dyeing devices, and the black fabric is especially serious, after down erosion (bio-enzyme treatment) of the polyester-cotton blend/cotton knitted shell fabrics. The processing method comprises the following steps: singeing ofgrey cloth, presetting, scouring, dyeing, washing and drying, and finalizing of the finished product. Raw materials of vortex spinning cotton yarns and the like are selected for yarns, and a mechanical singeing process is replaced by a bio-enzymatic etching process; the formula of a black monoazo disperse dye SFN, a stabilizer EL-SF and other assistant are used in dyeing polyester fibers, and dyeing cotton uses a super black M reactive dye G 300%. After the dyeing and finishing process, the color fastness indexes are excellent, the dust is very clean, the white color is not stained, and the cloth surface is smooth and clear in lines.