Abstract: Various factors possibly influencing the measurement of sulfate in simulated high level liquid waste (HLLW) by Raman spectroscopy were studied, such as integration time, duplicate folds, laser power and so on, and then the optimum conditions for the determination of sulfate were obtained. A method for determination of sulfate in simulated HLLW by Raman spectroscopy was described. The concentration of sulfate could be determined based on detecting the relative intensity between sulfate and water. The measurement range of sulfate concentration is within 1.15 g/L, the linear correlation coefficient r is 0.9996, the relative error is less than ±5%, and the detection limit is 0.05 g/L. While the method is simple and rapid, it does not need much chemical reagents. Thus, it could be used for detecting sulfate in HLLW.