Moslem chinensis Maxim, is a Labiatae Moslem, annual herb, is mainly produced in Guangxi, Guangdong, Sichuan, Guizhou, Hunan, Hubei and other places, are widely distributed in areas south of the Yangtze River in China in the north of the Yangtze River in some areas (such as Shandong,Anhui, etc.) and the distribution of important medicinal plants. In order to study thymol amassment characteristic of Moslem chinensis Maxim in different vegetation periods,supercritical CO2 extraction technology was used to extract main components of Moslem chinensis Maxim,and high-performance liquid chromatography(HPLC) was used to analyze thymol content in Moslem chinensis Maxim extract. The results showed that there is positive relationship between thymol amassment characteristic and growth period of Moslem chinensis Maxim. The thymol amassment characteristic can be divided into three periods of slow amassment period,rapid amassment period and stable period.