Objective:To analyze chlorogenic acid of Chaenomeles speciosa by high performance liquid chromatography-mass spectrometry. Methods:A method for determining chlorogenic acid of Chaenomeles speciosa by HPLC-MS is described. The operating conditions were Diamonsil C18 column (5μm, 4.6×250 mm) at room temperature, acetonitrile-0.05%phosphoric acid solution as mobile phase by step gradients elution at a flow of 0.8 ml/min and UV detection at 325 nm. Results: The content of chlorogenic acid of Chaenomeles speciosa is 1.3 mg/g (RSD 0.4%), respectively. Conclusion:Chlorogenic acid was detected from Chaenomeles speciosa, which may be related to its inhibition of FAS and the potential role of anticancer.