Abstract: Ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometer(UHPLC-QTOF MS) was applied to scan the main chemical constituents of distillation residues from cinnamon twigs and leaves. The molecular ion and characteristic fragment ions were detected in positive and negative ion modes. The fragmentation pathways of compounds were studied. The chemical constituents were characterized comprehensively by high resolution data and fragmentation of mass spectrometry. The results showed that UHPLC-QTOF MS can be used for rapid and comprehensive qualitative analysis of the chemical constituents from distillation residues. Total of 26 components of the residues were identified, including 2 polyphenols, 3 flavonoids, 5 glycosides, 4 alcohols, 3 aldehydes and 9 acids.