A rapid UHPLC-LTQ-Orbitrap MSn method was established for the identification of chemical profile in daylily flowers. Chromatographic separation was achieved on Hypersil Gold AQ RP-C18 column （100 mm×3.0 mm，1.9 μm） with the mobile phase of 0.1% formic acid-water and 0.1% acetonitril-water in gradient elution. High resolution mass spectrometry analyze the multilevel mass spectrometry data in positive ionization mode and qualitative the chemical profile. According to retention time， ultraviolet absorption， the accurate mass measurements， mass fragmentation patterns and literature reports， a total of 27 compounds including 12 phenolic acids， 15 flavonoids， and 1 other compound were tentatively screened and characterized. The method can efficiently， quickly， sensitively and comprehensively analyze the chemical profile of daylily， and provide a theoretical basis for the study of the pharmacological of daylily. Moreover， it could be useful for the structural identification of similar compounds.