Objective To extract and identify the chemical constituents of Rabdosia japonica. Methods The constituents were isolated and purified by chromatography on silica gel, Sephadex LH-20 and HPLC. The structures of the compounds were determined by mass spectrometry (MS) and nuclear magnetic resonance (NMR) spectra1 analysis. Results Totally 10 compounds were isolated and their structures were identified as four triterpenoids: oleanolic acid (1), ursolic acid (2), 2α-hydroxyursolic acid (3), 2α, 23-dihydroxyursolic acid (4)；six flavonoids:quercetin (5), apiginin (6), luteolin (7), rutin (8), isorhamnetin (9), and tricin (10). Conclusion Isorhamnetin (9) and tricin (10) had been isolated from this plant for the first time