Abstract： Objective To observe the dynamic changes of tumor necrosis factor-α (TNF-α)level in the plasma of renovascular hypertensive rots during the development of hypertension and detemine the possibility of TNF-α as an predictor in the cerebral vessel events. Methods Two-kidney two-clip renovascular hypertension was induced in 45 male SD rats as hypertension (H) group; another 15 rats were employed as sham-operated (SO) group. The systolic blood pressure of preheated conscious rats (37 ℃, 15 minutes) was measured by an indirect tail-cuff sphygmomanometer. The level of TNF-α in the serum was measured by enzyme-linked immunosorbant assay at pre-operation, and 2, 4, 8, 12, 16 w after the operation. Sixteen w after the operation, 2 mm-thick coronal section of brain tissue were stained with hematoxylin-eosin for routine light microsopic observation. Based on the pathological results of cerebral vessels, the H group was subdivided into isolated hypertension (IH) group and hypertensive cerebral vessels lesion (HCVL) group. Results The postoperative blood pressure (BP) and level of TNF-α in the H group were elevated and time-dependent after the operation with significant differences between any 2 time points (P<0.05). The blood pressure and the level of TNF-α in the H group were remarkly higher than those in the SO group at corresponding periods (P<0.05). The postoperative BP in the IH group was gradually advanced, while that in the HCVL group kept increasing and significant differences were noted between any 2 time points (P<0.05). The level of TNF-α in the HCVL group were increased 2 w after operation and strikingly higher than that in the IH group from 4 to 16 w (P<0.05). Conclusions TNF-α, involving in the development of hypertension, may connect to the happening of atherosclerosis and stroke. Up-regulative level of TNF-α may play a precaution role in the process of stroke in patients with hypertension.