OBJECTIVE： To establish pre- column derivatization-HPLC fingerprint of polysaccharide from Achyranthes bidentata，and to determine the contents of monosaccharide components ，so as to provide reference for quality evaluation of A. bidentata decoction pieces. METHODS ：Taking 10 batches of A. bidentata decoction pieces from different manufacturers as samples，the polysaccharides were extracted by water extraction and alcohol precipitation ，hydrolyzed by trifluoroacetic acid ，and then derivatized by 1-phenyl-3-methyl-5-pyrazolone for HPLC analysis. The determination was performed on Hanbon Hedera C 18 column with column temperature of 30 ℃ at the flow rate of 1.2 mL/min. The mobile phase consisted of acetonitrile- 0.02 mol/L ammonium acetate solution （gradient elution ）. The detection wavelength was set at 250 nm，and sample size was 20 μL. HPLC fingerprint was established and similarity evaluation was performed for 10 batches of A. bidentata polysaccharide by using TCM Chromatogramic Fingerprint Similarity Evaluation System （2012A edition ）. The common peak was identified by comparing with the reference substance ，and cluster analysis was performed by using SPSS 25.0 software. The contents of identified monosaccharides were determined by HPLC. RESULTS ：The similarity of 10 batches of A. bidentata polysaccharide were all higher than 0.95. Nine common peaks were fixed and a total of 5 common peaks were identified ，namely anhydrous glucose （peak 1）， mannose（peak 2），rhamnose（peak 4），galacturonic acid （peak 5）and arabinose （peak 7）. Results of cluster analysis showed that S1 sample was classified into one category ；S2，S5，S8 and S 9 samples were clustered into one category ；S3，S4，S6，S7 and S10 samples were clustered into one category. Results of content determination showed that the contents of anhydrous glucose in 10 batches of samples ranged from 6.17 to 17.55 mg/g；those of mannose ranged from 3.31 to 7.66 mg/g；those of rhamnose ranged from 38.80 to 73.97 mg/g；those of galacturonic acid ranged from 2.49 to 8.95 mg/g；those of arabinose ranged from 11.30 to 28.58 mg/g. CONCLUSIONS ：Established pre-column derivatization HPLC fingerprints and content determination method can provide reference for quality evaluation of A. bidentata decoction pieces.