Abstract: It is aimed to produce cotton fibers and fabrics containing thereof, which are excellent in dyeability and has gloss on surfaces and soft touch, or in otherwise to produce cotton-regenerated cellulose composite fiber product that has improved coloring evenness between the cotton fibers and the regenerated cellulose while keeping soft touch and sufficint dyeability. Yarns, fabrics or the like is subjected to processing with aqueous solution of alkaline metal hydroxide having surface tension of no more than 75 dyn/cm2; the processing being made under no tensile stress until static friction coefficient of the cotton fibers become 50 to 75% of that before the processing, or the processing being made under tensile stress until the static friction coefficient become 40 to 65% of that before the processing.