Introduction: Phospholipase A2 (PLA2) activity in the arterial wall may contribute to atherosclerosis by hydrolysis of the phospholipid monolayer in apo B-lipoprotein. Expression of Group V and IIa PLA2 may be different according to the atherogenic conditions. We evaluated the association between intimal thickness of carotid artery and the degree of enzymatic activity and localization of PLA2 in spontaneous hypertensive rat. Methods: Intimal thickness (IT) and Intimal media Thickness (IMT) of the common carotid artery were measured in the tissue stained with Masson Trichrome in 10 Wistar-Kyoto rats (Group I), 15 spontaneous hypertensive rats (SHR) fed a standard diet (group II), and 10 SHR fed a high-fat diet (group III). Immunohistochemical (IH) staining was done for the localization of GV and GIIa secretory PLA2 in the carotid tissue. The difference of enzymatic activity of G V and G IIa PLA2 were also determined by western blot in the carotid artery among the three groups. Result: 1. IT and IMT of the group II and III (IT: 53 짹 2關m and 58 짹 14關m, IMT: 72짹2關m and 74 짹11關m) were larger than Group I (IT:12 짹 1關m, IMT: 24짹3關m), respectively ( p���0.05,respectively). IH staining for G V and G IIa secretory PLA2 was noted abundantly at the intima correspondent with intimal thickness in the carotid artery. (Figure) The enzymatic activity of G IIa PLA2 was higher than G V PLA2 in SHR. But in the SHR with high fat diet, GV PLA2 rather than GIIa PLA2 was more abundantly expressed Conclusion: Group V and IIa secretory PLA2 are more expressed at intima in SHR and SHR fed a high fat diet compared to normotensive rat. Enzymatic activity of PLA2 is differently expressed according to the hypertensive and dyslipidemic conditions