Abstract: Bibenzyls are biologically active compounds widely found in Dendrobii Caulis.A HPLC method was developed for the determination of two specific bibenzyls，moscatilin and gigantol.Chromatographic separation was performed on a reverse-phase C₁₈ column employing a binary linear gradient elution with acetonitrile and 0.01% trifluroacetic acid.The linear ranges of moscatilin and gigantol were from 2.29 μg/mL to 1 144.00 μg/mL and 1.79 μg/mL to 1 196.00 μg/mL respectively with good correlation coefficients greater than 0.999 7.The average recoveries measured at three levels were 102.7% and 99.1%，respectively.The validated method was applied for 18 different species of Dendrobium plants and 18 batches of Dendrobii Caulis，which proved to be sensitive，reliable and applicable for the quality control.