The present invention relates to the production of textiles and more particularly pertains to a method for manufacturing cotton towels comprising the steps of: combining a yarn of 120S combed long staple cotton and a yarn of 10S combed long staple cotton by means of a double winder and winding onto a bobbin or bobbins after combining; feeding the bobbin or bobbins of the combined yarn into a double twister for plying; winding the plied yarn onto a bobbin and weaving into greige; impregnating the greige in the solution of a combined desizing, scouring and bleaching machine to be soaked and steamed for removing the sizes and the impurities in the cotton yarn; treating the greige by means of deoxidization, dyeing, enzymatic desizing, softening, relaxation drying and sewing into towels. The present invention adopts the 120S combed long staple cotton for plying which achieves a definitive binding effect on the loosened fibers on the surfaces of the yarn, thereby forming fewer fluffs on the surfaces of the towel. The present invention eliminates the step of removing the water-soluble filaments, reduces the labor intensiveness of the workers, relieves the pressure on the sewage treatment and alleviates the problems of the environmental pollution.