Abstract: Mogrol is the aglycone of seven kinds of mogrosides and siamenoside I. Mogrol has drawn more attention in recent years for its anti-leukemia and anti-diabetes activities. An ultra-high performance liquid chromatography/quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF/MS) method was applied to identify the main metabolites of mogrol in rat plasma. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for determination of the main components in rat plasma. After an oral administration of 100 mg·kg^-1 mogrol in rats, 13 metabolites were detected along the main component of parent drug in the plasma. The major metabolites were oxidated and dehydrogenated products. In this study, mogrol was quantitative analyzed using lithium carbonate reagent with high sensitivity. The assay was linear in concentration range 5.00-1 000 ng·mL^-1 with intra-and inter-day precision within 9.3% and accuracy in range of -4.5% to 2.9%. Mogrol was absorbed into the blood very fast after oral administration, and the time to reach maximum concentration (t_max) was 1.67 h. The half-life (t_1/2) of mogrol in rats was 2.34 h, and the oral absolute bioavailability was 3.5%.