The flower of Hibiseu manihot L. has rich flavonoid compositions which have high utilization value in food,medicine and health care.To compare the chemical composition differences in the flowers of H. manihot with different medicinal methods and determine the best medicinal period of H. manihot This experiment uses ultra-high performance liquid chromatography quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) analyzed the complete components of dried flowers,buds and fresh flowers of H. manihot.A total of 141 compounds were identified.Some of the flavonoids and organic acid compounds in the fresh flowers were higher than those in dried flowers and buds.In addition,fresh flowers and dried flowers have more medicinal ingredients and higher content than buds.The results showed that there are differences in the chemical composition of the flowers in different ways of medicine,and it should be picked and used according to the needs.All in all,this research provides a theoretical basis for the rational development and utilization of H. manihot.