Aim To investigate the relationship between carotid atherosclerosis in elderly patients and the expression of forkhead/winged helix transcription factor p3 （Foxp3）, and high sensitivity C reactive protein （hs-CRP） in peripheral blood. Methods 66 cases of elderly patients with carotid atherosclerosis and 51 healthy controls were detected by flow cytometry of peripheral blood Foxp3, nephelometry hair testing hs-CPR. Results Perpheral CD^4＋CD25^＋Foxp3 regulatory T lymphocytes in elderly patients with carotid atherosclerosis decreased significantly and increased after rosuvatatin treatment, significantly higher than that before treatment serum hs-CRP in patients with carotid atherosclerosis was significantly higher than that of the control group, hs-CRP in patients with carotid artery plaque were significantly higher than that in patients with carotid artery intima-media thickness Foxp3 was correlated negatively with hs-CRP. Conclusions Carotid atherosclerosis in the elderly patients are closely related with peripheral blood expression of Foxp3 and hs-CRP. The peripheral blood Foxp3 and hs-CRP play an important role in the occurrence and development of plaque formation in carotid atherosclerosis, and the control of these risk factors is beneficial to controling and reducing the occurrence of apoplexy.