Abstract: The ultra-high performance liquid chromatography-quadrupole-time of flight mass spectrometry (UPLC-Q-TOF/MS) coupled with the UNIFI database was developed and applied to efficiently and comprehensively identify the chemical constituents of ancient Eurya alata Kobuski leaves (Jigong mountain, Xinyang city, E114°01'-114°06', N31°46'-31°52'). The compounds structures were identified based on accurate molecular weight, parent ions, mass characteristic fragment ions, the law of mass spectrometry, along with the data from the UNIFI database, reference substances and literature. Totally, 29 compounds were extracted and confirmed from the ancient Eurya alata Kobuski leaves, including 1 oligosaccharide, 7 phenolic acids, 18 flavonoids, 2 anthraquinones and 1 terpenoid.