Thin layer chromatography (TLC) and gas chromatography-mass spectrometry (GC-MS) were used to identify moxa floss adulterant.Methods:The authentic moxa floss and adulterant were heated under reflux with petroleum ether (60~90 ℃)，evaporated to dryness，and then dissolved in cyclohexane to yield the test solution.The reference Folium Artemisiae Argyi was used to prepare the reference solution with the same method.A total of 2 μL of test solution and 2 μL of reference solution were respectively dripped on the same Merck TLC silica gel plate and reversed-phase TLC silica gel precoated plate and observed under sunlight and ultraviolet light (365 nm).GC-MS was used to determine the volatile oil constituents of moxa floss and gas chromatograms of the authentic product and the adulterant were compared.Results:Silica gel TLC plate and C18 reversed-phase TLC plate showed specific spots under sunlight and ultraviolet light (365 nm).According to the gas chromatograms，the content of volatile oil constituents was different between the authentic moxa floss and the adulterant and pentadecane and chamazulen which were found in the adulterant failed to be detected in authentic moxa floss.Conclusion:Silica gel TLC and C18 reversed-phase TLC can quickly and accurately distinguish moxa floss adulterant，with stable result.GC-MS can be used to detect the differential components in the adulterant.