Polypropylene fibers don’t have comfortable properties such as moisture absorption, dye absorption and good handle. Blending to produce blend composite fibers is a method for modifying properties of synthetic fibers. Another method is modifying of synthetic fibers properties with modifier materials such as nano organoclay and nano carbon. In this paper the effect of compatibilizer (PP-g-MAH) and nano organoclay Closite 15A on the microfibrillar structure of Polypropylene / Polyamide6 nanocomposite fiber were investigated. The samples with the same blend ratio (PP/PA6 70/30) but varying in organoclay content (3, 5 percent) was prepared with and without the compatibilizer by using a melt compounding process in an internal mixer. The blended samples melt spun in a single screw extruder to prepare the blend fibers. The organocally partitioning and microfibrillar morphology development of PP/PA6 nanocomposite fibers were studied with wide angle X-ray diffraction (WAXD) and scanning electron microscopy (SEM). The results show that the sizes of PA6 disperse particles and nano organoclay intercalation and/or exfoliation on the blend nannocomposite was controlled by nano organoclay percentages and presence or absence of compatibilizer. Furthermore the dyeability of PP/PA6 nanocomposite fibers with Acid milling dye is modified and increased on exhustion dyeing bath in the presence of nano organoclay.