Objective To investigate the changes and correlation between platelet activation and inflammatory response in patients with essential hypertension(EH). Methods Sixty-one patients with essential hypertension and sixty-four patients with paroxysmal supraventricular tachycardia as control group were enrolled in the study. The levels of high sensitivity C reactive protein ( hs-CRP ) and mean platelet volume ( MPV ) were measured and compared between the control group and the essential hypertension group. Results Compared with the control group,the levels of hs-CRP and MPV in the EH group were significantly higher( [3.51 ± 1.95]mg/L vs [ 1.15 ± 0. 77 ] mg/L, P ＜ 0. 05 ). The MPV in the EH group was significantly higher than that in the control group ( [ 11.29 ± 2. 18 ] flvs [ 9. 20 ± 2. 31 ] fl, P ＜ 0. 05 ). The level of hs-CRP positively correlated to the level of M PV (r = 0. 452, P = 0. 003 ). Conlusions There were inflammatory response and platelet activation in patients with EH and the serum levels of hs-CRP and MPV is correlated with the development of essential hypertension.