Objective To study the level of cyclooxygenase-2 (COX-2) and platelet-activating factor acetyl-hydrolase(PAF-AH) and high sensitive C reactive protein(hsCRP) on peripheral blood mononuclear cells in Acute Coronary Syndrome(ACS) patients and the effect of atorvastatin on them and the clinical significance. Methods To measure and compare the content of COX-2,PAF-AH and hsCRP in normal control group and ACS group(before and after treatment). Result The content of COX-2,PAF-AH and hsCRP are significantly different between normal con-trol group and ACS group (before treatment) (P < 0.05), and between ACS group (before treatment) and ACS group (after treatment) too(P < 0.05). Conclusions The inflammatory cytokines COX-2,PAF-AH and haCRP have sig-nificant correlation with the occurance of ACS. Atorvastatin can decrease COX-2 and hsCRP level, and can increase PAF-AH level. So atorvastatin takes an important role in lessening inflamatory reaction level in ACS patients.