Abstract: Near infrared reflectance spectroscopy technique was employed to measure the polysaccharides of Chinese herb extracts rapidly.The experiment had measured the content of polysaccharides in the 102 groups of the oral liquid of Chinese herb extracts, adopts the partial least squares method combined with the polysaccharides chemical reference values, and establishes the optimal model of measuring the polysaccharides of the oral liquid by the near infrared reflectance spectroscopy technique, which was obtained by comparing method and derivative of different preprocessing and the size, waveband and variable selection way of the smooth window on the predictive ability of the above model: the pre-processing method of spectrum wasthe combination of the first derivative and smooth process, and their moving window widths were 5 and 9respectively.The chosen wavebands contained 5079.58 ~ 5152.86, 6159.52 ~ 6232.80, 6545.21 ~ 6695.63, 7470.88 ~ 7544.16 and8705.09 ⁸778.38 cm^-1 in the sum of 120 variables.The root-mean-square error of the model cross validation was 15.4823, and the root-mean-square error of the model prediction was 16.2807.The results showed that the method for rapidly measuring the polysaccharides in oral liquid based on the combination of the near infrared reflectance spectroscopy technique and chemometrics method was of certain feasibility.