Aim To investigate serum heart-type fatty acid-binding protein （H-FABP） and ischemia modified albumin （IMA） in early diagnosis and severity judgement in patients with acute myocardial infarction （AMI）. Methods 92 patients admission into hospital with acute chest pain in 6 hours were selected as the patient group, and they were verified by coronary angiography. The patients were divided into AMI group （54 patients）, unstable angina pectoris （UAP） group （21 patients） and stable angina pectoris （SAP） group （17 patients）. At the same time, 20 healthy people were selected as health control group. Blood samples of the patients and the control group were collected for test of CK-MB, cTnT, IMA and H-FABP. The results of ROC curve analysis was used to determine the optimal cut-off of this assay for identifying individuals with AMI and non-AMI. Results The levels of H-FABP and IMA in AMI patients were significantly higher than those in the other three group the levels of H-FABP and IMA in UAP group and SAP group were higher than those in the control group （P<0.05）. ROC curve of H-FABP and IMA showed the area under ROC curve was 0.967 and 0.904, the sensitivity in AMI diagnosis was 92.6% and 96.3%, they were significantly higher than cTnT （83.3%） and CK-MB （79.6%）. H-FABP and IMA serum levels in Gensini scores≥40 was significantly higher than those in 20～40 scores group and 0～20 scores group （P<0.05）. H-FABP and IMA serum levels in three-branch group had significance difference than those in double-branch group and single-branch group （P<0.05）. Conclusions Serum levels of H-FABP and IMA had higher sensitivity and specificity in AMI diagnosis and it was related to the severity of coronary artery disease. Serum H-FABP and IMA and the other biochemistry markers simultaneously was very useful to the early diagnosis, sensitivity judgement of the ACS.