The invention relates to polyester knitting warp-yarn eiderdown shell fabric and a processing method thereof, belonging to the technical field of polyester fiber products. The polyester knitting warp-yarn eiderdown shell fabric comprises operability surface yarn textures and bottom yarn textures. The surface yarn textures utilize the raw materials of 150D/288F polyester superfine flat low stretch yarns, and the bottom yarn tissues utilize the raw materials of 75D/36F polyester filament yarns. The invention adopts the technical scheme that the 150D/288F polyester superfine flat low stretch yarns are preferentially utilized as the raw materials of the surface yarn tissues, and the 75D/36F polyester filament yarns are utilized as the raw materials of the bottom yarn tissues, so the shell fabric not only has the advantages of heat preservation, crease resistance, insect prevention and moth resistance of polyester coral fleece, but also has ideal soft and smooth feeling. The polyester knitting warp-yarn eiderdown shell fabric has the characteristics of rich and fluffy fluff, and lightness and elegance like eiderdown, and can permanently keep the effect of the characteristics. The provided processing method has a few technique links and saves labor investment and energy source as well. Moreover, the flaw generation rate is reduced due to the few technique links.