The content of oleanolic acid was detected by HPLC and the extraction method of oleanolic acid from Chinese flowering quince was investigated. The optimal extraction results were got with organic solvent such as water-free ethanol. That oleanolic acid distributed mainly in residues and undetectable oleanolic acid distributed in Chinese flowering quince syrup were found through detection of variety samples of Chinese flowering quince fruit vinegar. Functional fruit vinegar with oleanolic acid can only be pro...