Recycled poly(ethylene terephthalate) (RPET) is now prompt for utilizing regarding to environment consideration. In this study, bicomponent fiber of recycled poly(ethylene terephthalate) (RPET) and polyamide 6 (nylon 6) is prepared using bicomponent fiber machine. The characteristics of bicomponent fiber are side by side and core/sheath structure, which the ratios of RPET/PA6 side by side are 10/90, 30/70, 50/50, 70/30 and 90/10. The barrel temperature is set at 260-290 C. Fiber take speeds are 1,000 and 1,200 m/min. The effects of RPET/PA6 ratios and fiber take up speeds on structure, fiber orientation, mechanical performance and thermal properties are investigated. Optical microscope of fibers cross section shows parts of melt spun bicomponent fibers closely to the setting ratio. Crystallization temperature and crystallinity of RPET in the bicomponent is higher than in neat RPET fiber, which nylon 6 might aid PET crystallization. Tenacity and elongation of the bicomponents fiber are elucidated as a function of RPET/nylon6 ratio and structure of the bicomponent fiber.