Objective: To establish the quantification method of water-soluble polysaccharide and alkali-soluble polysaccharide in Poria by near infrared spectroscopy (NIR). Method: Optimization of the extract method about water-soluble polysaccharide and alkali-soluble polysaccharide was carried out. Meanwhile quantification method with phenol-concentrated sulfuric acid colorimetric reagent was established and the contents of water-soluble polysaccharide and alkali-soluble polysaccharide of ninety batches of samples were obtained. Near-infrared diffused reflected spectroscopy was implemented to obtain the NIR spectra of Poria. The NIR method was established by referring to the obtained contents with partial least squares regression (PLS) to pretreat the NIR spectra and with the program named synergy interval partial least squares regression (SIPLS) over Metlab R2012a platform to select sensitive wavelength number. And parameters was optimized by investigating the root-mean-square error of prediction (RMSEP) the correlation coefficient of calibration (Rc2)

the root-mean-squares error of cross-validation (RMSECV) and the correlation coefficient of prediction (Rp2). Result: The RMSEC value of water-soluble polysaccharide is 0.270

the Rc2 value is 0.905 9

the RMSEP value is 0.119

the value of Rp2 is 0.913 8.Regarding to alkali-soluble polysaccharide

the RMSEC value is 0.242

the Rc2 value is 0.999 6

the RMSEP value is 0.243

and the value of Rp2 is 0.998 9. Conclusion: The established NIR method is convenience and accurate and satisfies the requirement of the rapid quality evaluation of Poria.