The dyeing ability of the polypropylene (PP) fiber was modified by blending with poly(lactic acid) (PLA). The PP, PLA, and PP/PLA fiber were obtained using the melt-spinning technique in the presence of the polypropylene-graft-maleic anhydride as a coupling. The dyeing ability, mechanical and thermal properties, and crystalline structure of the PP, PLA, and PP/PLA fibers were investigated. The effect of dyeing ability was measured using the CIE L * a * b * . The a* value of the PP of 11.91 increased to 43.48 for PP/PLA90, showing a light pink to red color. The SEM images demonstrated smooth fiber with color coating on the fiber. The mechanical property of the fiber indicates that increasing the PLA decreased the tenacity of the PP fiber. The melting behavior of fiber increased with the PLA. The XRD presented the PP's crystalline and the PLA's amorphous structures.