In this study, microorganism separated from the Syrian soil were used in treating the waste water from dyehouse and some dyes which are oftenly applied. A great difference was found in the speed of microorganism growth as well as the great variation in color disappearance, in addition to inactivating the enzymatic work by some of the dyes. Also, the effect of the dyes density on the growth of microorganism. The absorption strength measurment in the field of visible spectrum between ٣٥٠ –٧٥٠ nanometers was adopted for analyzing the filtrates resulting from the biological treatment .