Objective: To establish an ultra-high performance liquid chromatography-triple quadrupole tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous determination of ten flavonoids in Dendrobii Officinalis Caulis and compare the flavonoids and polysaccharide contents in samples from different habitats. Method: The determination was carried out by an ACQUITY UPLC BEH C18 (2.1 mm×100 mm

1.8 μm)

with 0.1% formic acid-water (A) and 0.1% formic acid-acetonitrile (B) as mobile phase for gradient elution. The flow rate was 0.6 mL · min-1

and the column temperature was 40 ℃. MS instrument was equipped with ESI- ion source

and the extracted ion chromatograms were obtained with negative ion detection mode

quantified by using peak area. Result: The ten flavonoid components had good linearity

r>0.998 5

and the precision

repeatability

stability and accuracy of the established method were well-validated

RSD<3%. The recovery was 96.6%-104.7%

RSD<3.5%. The results showed that there were significant differences in the composition and content of flavonoids in Dendrobii Officinalis Caulis from different habitats; the contents of polysaccharide and mannose in the 14 batches of samples were consistent with the pharmacopoeia standards. Conclusion: The established method is proved to be rapid

accurate and sensitive for the determination of flavonoids content in Dendrobii Officinalis Caulis. Moreover

the quantitative results combined with Chinese Pharmacopoeia indexes may provide basis or the improvement of quality standards of this herbal medicine.