ObjectiveTo use rapid-resolution liquid chromatography-time of flight mass spectrometry (RRLC-TOF/MS) for analyzing the chemical constituents of epimedium. MethodsThe separation was performed on a SHISEIDO MG C18 reverse phase column (3.0 mm×100 mm, 3 μm).The mobile phase consisted of water containing 0.1% formic acid; acetonitrile was used as gradient elute.The gradient of A phase was as following: 5%-19%(0-3 min), 19%-32%(3-13 min), 32%-52% (13-25 min), and 52%-70% (25-30 min). The flow rate was 0.6 ml/min, post-column split ratio was 31, and the temperature of column was 25℃. Time-of-flight mass spectrometer(TOF/MS) and electrospray ion source (ESI) was applied for qualitative analysis under the positive ion mode, and mass scan range was m/z 100-1 000. ResultsA total of 43 chemical constituents were identifled from epimedium by RRLC-TOF/MS in one run. ConclusionA rapid and efficient RRLC-TOF/MS approach for identifying the chemical constituents of epimedium has been successfully established, which paves a way for quality control and further in vivo studies of epimedium.