In this study, an attempt was taken to dye conventional and microfibre polyester filaments with disperse dye and evaluate their different dyeing effects in similar dyeing condition.The main attention was given to find out K/S values, color difference and different colorfastness properties (light and wash fastness) and also the amount of dyes addition required for microfibre polyester filaments to get the same depth of shade as conventional one’s.There were three different hues (Red, Navy and Green) of 5 different shades (0.5%, 1.5%,3%, 4% and 6%) were used. The result shows that, microfibre polyester requires higher amount of dyes due to more surface area and greater absorbing capability of it. Almost similar light fastness was found in both conventional and microfibre polyester filaments and lower wash fastness properties of microfibre filaments when compared to those of conventional polyester.