A simple and rapid spectropholometric method for the determination of sodium dodecyl sulphate ISDSI, an anionic surfactant (AS) is developed. SDS forms a yellow Coloured complex with acridine orange (ACO), a cationic dye. The complex is extracted in toluene. The absorbance of the complex in toluene layer is measured at maximum wavelength (lambda(max)) of 467 nm. The calibration curve is linear in the range of 0 - 6.0 ppm of SDS concentration. The method is compared with the standard MBAS method in terms of time, ease and accuracy. It is noticed that the present method is much easier and less time constuming. The method requires chemicals, which are less toxic than those required for the standard method. The method is applicable to wastewater analysis.