Abstract: An object is to provide a high performance liquid chromatography method which enables quantitative analysis with the stability of reduced pyrroloquinoline quinone under measurement conditions maintained. The object can be achieved by the following method. A high performance liquid chromatography analysis method, comprising: a sample preparation step of preparing a sample for high performance liquid chromatography containing reduced pyrroloquinoline quinone or a salt thereof from a specimen and a separation step of separating the reduced pyrroloquinoline quinone or a salt thereof contained in the sample for high performance liquid chromatography from the specimen using interaction between a stationary phase and a mobile phase by a high performance liquid chromatography method using a reversed phase column as the stationary phase and using an eluent comprising 0.050 to 1.5% by mass of phosphoric acid and/or hydrochloric acid and 20 to 50% by volume of methanol and/or acetonitrile as the mobile phase.