This study reported the identification and determination of the main components of Commelina communis Linn. A total of 62 compounds were identified in C. communis Linn. extract, which included 29 flavonoids and flavonoid glycosides, 17 phenolic acids, 4 alkaloids, 1 pyrimidine alkaloids, 3 sterols and 8 fatty acids and others by ultra high performance liquid chromatography coupled with hybrid triple quadrupole time-of-flight mass spectrometry. Moreover, a specific, simple, rapid and sensitive high performance liquid chromatography with tandem mass spectrometry method was developed and validated for determination of 13 components of C. communis Linn., which included orientin, iso-orientin, vitexin, isovitexin, rutin, apigenin, protocatechuate, vanillic acid, caffeic acid, ferulic acid, luteolin, quercetin and isorhamnetin. All calibration curves showed good linearity (r ≥ 0.9991) within the test range. The intra- and inter-day precisions (relative standard deviation%, RSD%) were within 1.04 and 0.92%, and the recoveries ranged from 98.64 to 100.8%. These results may contribute to the further study and quality control for C. communis Linn.