Objective: To rapidly determine the contents of paeonol and water in Moutan Cortex using near infrared (NIR) spectroscopy combined with partial least squares (PLS). Method: 108 batches of Moutan Cortex samples were collected from different regions of China. Near infrared spectrum correction models were established using PLS method for determination of paeonol and water content. The reference analyses were performed with oven-drying method and ultra performance liquid chromatography method respectively for water and paeonol content. Correlation coefficient and predicted root mean square error were also used for evaluating the estimated performance of the models. Result: The correlation coefficients for calibration set were 0.9593 and 0.8738 respectively for paeonol and water content;root mean square error of calibration was 0.114 and 0.167

respectively;root mean square error of prediction set was 0.136 and 0.157

respectively. Conclusion: This method is rapid

simple

and has no pollution

which can be used for rapid determination of paeonol and water in Moutan Cortex.