Today auxiliary and cooperative materials, play a very important role in dyeing and textile manufacturing by increasing quality of products in this competitive market. These materials save costs by increasing production efficiency and reducing waste. Dispersants are one of the most widely used auxiliary in the textile industry. Dispersants are so important in polyester dyeing with disperse dyes which are known as agents for improving and increasing the migration and uniformity of disperse dyes to polyester fibers. Instability of dispersion causes the accumulation of dyes on textile fibers in an aqueous environment. It reduces the color fastness and ultimately lowers the quality of the textile. To prevent these problems, controlling the quality of dispersing materials is important in factories which are the basis of this research. In this article, we try to investigate the dispersers used in industrial plants by scientific and standard methods also empirical methods. Filter test, levelling test, colorfastness to crocking test, sedimentation test, foam test and turbidity test on dispersers in the laboratory and production line were performed to control the quality of dispersant materials.