Abstract: Objective To investigate the serum calcium(Ca²⁺),sodium(Na⁺),potassium(K⁺)contents and their effects on incidence of hype rtension for prevention of hype rtension.Methods Fromroutine health checkup examinees,56 essential hyertansion patients and 56 age-matched healthy persons were randomly selected for the case-control study.The contents of serum Ca²⁺,Na⁺,K⁺ were measured with flame a tomic absorption spectrop hotometry.Partial correlation and linear model were adopted in the analysis.Results A fter ad justed for age and gender,the weight,body mass index(BMI),waist circum ference,hipcircum ference,a rmcircum ferencet,riglyce rides were positively correlated with sys to lic and dias to lic blood pressure(P<0.05)and the high density lipoprotein(HDL-c),serum Ca²⁺,K⁺ concentrations were negatively correlated with systolic and diastolic blood pressure(P<0.05).The weight,BM I,waist circum ference,hipcircum ference,upper armcircum ference of the cases were higher than that of controls(P<0.05)and serum K⁺ content of the cases was significantly lower than that of the control group(P<0.01).The interactions between blood pressure and serum Ca²⁺ and K⁺,Ca²⁺ and Na⁺ were observed.Conclusion The serum Ca²⁺,Na⁺,K⁺ contents and Ca²⁺ and Na⁺,Ca²⁺ and K⁺ contents have a correaltion with blood pressure.The in take of potassium and calcium-rich food may have preventive effect on hypretention.