Textile wastewater is well known as one of the wastewaters to be most difficultly treated. The effects of niacin on textile wastewater niacin, the physical and chemical indexes of the water samples, such as COD, ammonia and dehydrogenase activities, were analyzed every day with standard methods, and obvious improvement in wastewater treatcould improve the COD removal efficiency signifcantly with removal rates mental condition, addition of niacin had almost no effect on the removal of ase by 130%. It proved that the biological treatment performance of textile wastewater treatment system probably could be optimized through micronutrient niacin supplement.