This application discloses a method of differentiating stable angina pectoris from acute coronary syndrome, including: obtaining a blood plasma sample from a patient; measuring a relative concentration of at least one metabolic biomarker in the blood plasma sample, wherein the at least one metabolic biomarker is selected from the group consisting of malic acid, taurine, arachidonic acid, citramalic acid, methionine, and pentadecanoic acid; calculating a value according to the relative concentration of at least one metabolic biomarker; comparing the value with a predefined critical value, if the value is more than the predefined critical value, the patient has the acute coronary syndrome, otherwise, the patient has the stable angina pectoris. The method and a diagnostic kit thereof is capable of differential diagnosis of SA and ACS and it can improve the diagnostic convenience and promote the diagnostic standardization.
