The present invention relates to a high performance liquid chromatography method for polypeptide mixtures. Specifically, the method including the following steps: step (1): preparing a solution of the glatiramer acetate to be tested; step (2): performing gradient elution on a sample to be tested with a reversed-phase liquid chromatography; step (3): determining a peak area corresponding to each component of the glatiramer acetate , comparing the peak area with to a peak area of a reference substance to determine whether the content of each component of the sample to be tested is in a qualified range.