Hypertension is a global cardiovascular diseases where treatment remains a major financial burden (Lloyd-Jones et al., 2009). Some studies have identified important aetologic factors while others on mechanisms focused on genetic factors and ATPase activities (Manesh et al., 1987) but the findings are inconclusive. Therefore, erythrocyte Na+/ K+ -ATPase activities were measured in 99 normotensive human subjects aged 16-30 years with and without family history of essential hypertension (FH/WF H). Na+/ K+ -ATPase activities were measured using inorganic phosphate (Pi) released from ATP hydrolysis. The level of Pi was determined by the method of Fiske and Subbarow (1925). Only subjects who consented and were medically fit were allowed in the study. Erythrocyte membrane preparation and protein estimation were determined using standard procedure (Hamlyn and Duffy, 1978; Stewart, 1974). Mean values + S.E.M were recorded in this study and statistical analysis was by student’s t-test. The results showed that in males with FH, Na+/ K+-ATPase activities were lower (13.46 + 1.242, n=35) than corresponding values WFH males (16.72+ 1.831, n= 64; p<0.0001). The Na+/K+-ATPase values in FH females and WFH females were not different. Furthermore, the systolic and diastolic blood pressure (SBP & DBP) values were not significantly different. It is therefore concluded that Na+/K+-AT Pase activities in hypertensive subjects with FH and WFH groups are familial and may underlie membrane cation transport in these subjects.