Abstract: Aim ：To investigate the chemical components in Zhizidahuang decoction(ZZDHD) to reveal the possible material therapeutic basis. Methods ：High performance liquid chromatography coupled with photodiode array detector and tandem mass spectrometry(HPLC-PDA-MS/MS) was applied to simultaneously characterize the chemical components and their structures in ZZDHD.The analysis was preformed on a Lichrospher C₁₈ column using a binary eluent of 0.1% acetic acid(A) and methanol(B) mixed under the gradient mode；UV spectra were scaned from 210 nm to 480 nm；negative ESI experiments in data-dependent scan mode were performed. Results ：HPLC-PDA-MS/MS chromatogram of ZZDHD was achieved.Based on UV spectral data，information of molecular weight and mass fragmentation behaviors connected with extracted ion current(EIC) chromatogram，twenty kinds of components were detected and identified，including flavonoids，anthraquinones，iridoids and other constituents. Conclusion ：The method presented in this study，which combined HPLC with UV and MS，allowes the characterization of compounds in the complex herbal system even without the reference standards.