Abstract: Objective:To analyze the variable coefficient difference of red blood cell distribution width(RDW) in different stage of elderly people essential hypertension and investigate the correlation between the level of essential hypertension and RDW.Methods:The levels of systolic blood pressure,diastolic blood pressure,RDW,blood urea nitrogen,uric acid,blood lipid and homocysteine of 191 senile patients with stage 1,2 and 3 essential hypertension were measured and analysed.Fifty-nine healthy people acted as the control group.The correlation between different hypertension level and the variable coefficient of RDW was investigated using linear correlation analysis and multiple linear stepwise regression.Results:There was not statistical significance in the variable coefficient difference of RDW of different stage hypertension(P0.05).The variable coefficient of RDW was positively related with systolic blood pressure.Multiple linear regression analysis showed that systolic blood pressure was a influencng factor of the variable coefficient of RDW(=0.351,P=0.002).Conclusions:The variable coefficient of RDW is not significant difference in different stage hypertension,which is positively related with systolic blood pressure.