Objective To observe the correlation between heart rate turbulence (HRT) and heart rate variability in patients with essential hypertension.Methods 50 cases of essential hypertension were selected and 30 healthy subjects were taken as controls.Turbulence onset (TO) and turbulence slope (TS) were calculafed according to 24 h Holter results of the two groups.The correlation between TO,TS and SDNN of 24 h RR,every-5-min of 24 h RR and rMSDD of RR as well as the correlation between TO and TS Was studied.Results TO in essential hypertension group Was remarkably higher than in control group but TS Was lower.TO and TS were correlated with SDNN, SDANN and rMSDD (r=-0.587,r=0.679,r=0.423,r=0.513,r=0.336,r=0.417)(P<0.05 respectively). Conclusion Systolic HRT before ventricular period is weakened in patients with essential hypertension.TS can be an index in evaluating autonomic nerve function of primary hypertension.