An analytical method was developed for the determination of contents of maleic acid (maleic anhydride) and fumaric acid in starch and related foods by high performance liquid chromatography(HPLC).The samples were extracted with 1% ammonia water-methanol solution(1∶1).The target compounds were separated on an Atlantis-T3 C18 column using 0.03 mol/L ammonium dihydrogen phosphate solution as mobile phase,and detected with diode-array detector.Under the optimized conditions.Two compounds were separated completely.The average spiked recoveries were in the range of 82.5%-103.5% with RSDs less than 4.3%.The limits of quantitation(LOQs) for maleic acid and fumaric acid were both 2.0 mg/kg.With the advantages of convenience,sensitivity,good recoveries and repeatability,the method was suitable for the detection of maleic acid(maleic anhydride) and fumaric acid in starch and related foods.