Background: Type 2 diabetes mellitus (T2DM) is an inflammatory atherosclerotic condition with high prevalence of cardiovascular disease. Elevated C-reactive protein (CRP) predicts cardiovascular events in T2DM patients. Objectives: Our work aimed to assess sensitivity and specificity of CRP in diagnosis and follow up of carotid atherosclerosis in T2DM patients (detected by measuring carotid intima-media thickness CIMT). Design and setting: It is observational cross sectional study on T2DM patients from outpatient clinic of fayoum university hospital. Subjects and methods: Hundred patients with T2DM were included; Group I: statin un-treated, Group II: statin treated, and fifty healthy control persons. Laboratory measurement of total cholesterol, LDL, HDL, and serum CRP levels and carotid duplex scanning were done. Results: The patients had higher levels of CRP and CIMT than control. There was strong correlation between CIMT and CRP level among group I and II. LDL in diagnosis of atherosclerosis disease illustrated sensitivity (80%) and specificity (4%), while HDL sensitivity (96%) and specificity (36%). CRP showed higher sensitivity (98%) and higher specificity (72%). Conclusion: CRP level was an important parameter of atherosclerosis with good sensitivity and specificity regardless the level of LDL and HDL.