the paper relates a study in developing a quantitative elemental analysis for clay minerals by the EDXRF technique. Elements of interest are Al, Si, K, Ca, Ti and Fe. The regression method involved development of calibration graphs of each of these elements using six different clay minerals reference standards. straight lines were obtained from these calibration graphs with r2 values ranging from 0.923 to 0.997. The accuracy of this regression method was then tested by comparing the quantitative analysis result obtained from fundamental parameter method using argillaceous limestone reference standard as the sample. Fundamental parameter method gives a more accurate result than that of the regression method.