OBJECTIVE To establish a comprehensive and rapid m ethod for the a nalysis of chemical constituents as phthalides and organic acids in Angelica sinensis ，and to provide scientific reference for the quality evaluation and pharmacodynamic substance research of A. sinensis . METHODS The 70％ ethanol extract of A. sinensis was analyzed by ultra high performance liquid chromatography-quadrupole-time of flight tandem mass spectrometry （UPLC-Q-TOF/MS）. The determination was performed on ACQUITY UPLC BEH-C 18 column with mobile phase consisted of 0.1％ formic acid solution- acetonitrile（gradient elution ）at the flow rate of 0.3 mL/min. The column temperature was set at 30 ℃，and sample size was 2 µL. The ion source was an electrospray ion source ，using positive ion scanning mode ，and the mass scanning range was m/z 50-1 000. Capillary voltage was 4 000 V； atomizer pressure was 35 psi；cracking voltage was 135 V and the taper hole voltage was 65 V；the temperature of dry gas was 320 ℃；the flow of dry gas was 10 L/min and the flow of sheath gas was 11 L/min；collision energy were 20 and 40 V. Qualitative Analysis 10.0 software was used to obtain the retention time of compounds ，the accurate mass number of excimer ion peaks and secondary fragments. The compounds were analyzed by comparing with the mass spectra of the reference substance ，combined with relevant literature ，mass spectrometry cleavage law and database such as Chemspider ，MassBank，PubChem. RESULTS A total of 72 compounds were identified or deduced from A. sinensis ，including 55 phthalides，13 organic acids and 4 other constituents. CONCLUSIONS The established method is rapid and accurate for the identification of chemical constituents from A. sinensis ，such as organic acids and phthalides ，which provides an efficient and rapid analytical method for the comprehensive characterization of its chemical constituents.