A simple, rapid and sensitive liquid chromatography-tandem mass spectrometry method was developed for quantification of deglymidodrine in human plasma. The plasma samples were pretreated by protein precipitation with trichloroacetate. The chromatographic separation was performed on reversed phase Aquasil C18 column, and the plasma extraction was eluted with a mobile phase solution consisting of acetonitrile (containing 0.02% formic acid) and water (containing 0.02% formic acid). The molecular ion of analyte was detected in positive ionization by multiple reaction monitoring. The mass transitions of m/z 198.4--> 148.1 and m/z 212.4--> 162.3 were used for detection of deglymidodrine and its internal standard, respectively. The assay exhibited linear ranges from 0.25 to 32 ng/ml for the analyte in human plasma. Acceptable precision and accuracy were obtained for concentrations of quality control (QC) samples. The proposed method has been successfully used to analyze human plasma samples for application in oral pharmacokinetic study.