This research aimed at scrutinizing the comparative dyeability of some disperse dyes at low temperature on ultra-microfiber polyester, islands in the sea type (0.05 denier), which has claimed utmost fastness and improved uptake of dyeing. Comparisons of dyeability, such as rate of dyeing and color depth, on ultra-microfiber polyester were evaluated by H.T. exhaust dyeing method and followed by the test of rubbing fastness. To achieve high wet fastness, some commercial disperse dyes, Terasil WW and Megacron dyes, which have been recently launched for excellent wash fastness, have been examined compared with conventional disperse dyes, C.I Disperse Red 167 and C.I Disperse Orange 30.