Since the polyjuice potion ingredient is complex, we need to develop an analysis method with well separation and high stability to perform qualitative analysis. After dividing chemical components of Mahuang Decoction into fat-soluble and water-soluble constituents by gradient extraction, GC-MS was used to analyze the chemical components of the ethyl acetate extraction. The results showed that forty compounds had been identified by NIST MS search 2.0 standard mass spectrometry Library and literatures. Next, UPLC-Q-TOF-MS was applied to idendify the chemical components of the water extraction. The results showed that thirty-nine compounds had been identified by MZmine-2.9.1, Isotope Pattern, fragmentation regularity of mass spectrometry and literatures. This experiment will provide evidences for elucidation of the effective substance in Mahuang decoction and can be used as a simple, shortcut method for analysis and identification for the polyjuice potion.