Acute coronary syndromes (ACS) like unstable angina (UA) and acute myocardial infarction (AMI) can lead to the morbidity and mortality. The diagnosis and management of patients with ACS in the earliest times after symptom onset are considerably important in the emergency service. Study aimed to investigate the serum levels of heat shock protein 70 (Hsp 70), high sensitivity C-reactive protein (hsCRP), total creatine kinase (CK) activity, creatine kinase MB (CK-MB), cardiac troponin I (cTnI), leukocyte count (WBCs) and markers of oxidative stress in the first hours of ACS and to view their diagnostic values. 70 patients with ACS after admission and 20 sex-matched healthy controls were included in this study. Serum Hsp 70, hsCRP, CK, CK-MB, cTnI, protein carbonyls, malondialdehyde as well as whole blood WBCs were measured. The level of hsCRP was statistically higher in patients with AMI and UA than that of control group (p<0.001). WBCs and oxidized protein levels were higher in AMI than in UA and control groups. cTnI was related to CK-MB in AMI and UA groups (r=0.731, r=0.806, p<0.001, respectively) and also related with hsCRP in UA group (r=0.824, p<0.001). The mean Hsp 70 level was higher by 32.2% in AMI and 12.7% in UA patients compared to control subjects. hsCRP may have a role in the inflammatory response after ACS. In addition to cTnI and CK-MB, WBCs and hsCRP may be useful as a marker for the identification of ACS patients with chest pain in early diagnosing.