Components of the Lespedeza cuneate from three different months were extracted by ultrasonic alcohol extraction method, the extractives were dissolved by ether and analyzed by GC MS, and quantitative analysis of lupenone by GC MS. Results showed that 61 components have been detected. Lespedeza cuneate included 42 components in May, 39 components in August and 42 components in November. The mainly include alkane, terpenoid and aromatics. The lupenone was firstly found in Lespedeza cuneate, and the relative contents of lupenone in May, August and November were respectively 1.734mg/g, 2.235mg/g and 1.111mg/g. Through comparison the Lespedeza cuneate constituents and contents of the three different months, the Lespedeza cuneate constituents was the least in August, but the contents of it is the highest.
