In this study, the properties of 1,4-cyclohexanedimethanol (CHDM)-modified polyethylene terephthalate (PET) were investigated with several techniques. The spinning conditions of the copolyester fibers were discussed in detail. The results revealed that the glass transition temperature and melt index of the copolyesters were increased with an increasing CHDM content. The weight loss of the copolyesters was lower than that of regular PET (semi dull, SD). The copolyester fibers had lower tenacity, modulus, and weight loss than SD. The elongation of the copolyester fibers was lower than that of SD when the spinning speed was lower than 3500m/min. The crystallinity of the copolyester fibers decreased with an increasing CHDM content. The copolyester fibers showed a high surface color difference (K/S) value compared with SD fibers in the same conditions.