The renin-angiotensin system is a major regulatory system of cardiovascular and renal function. Recently, (pro)renin receptor [(P)RR] was identified as new component of the renin-angiotensin system. The IVS5+169C>T polymorphism of the (P)RR gene was shown to be associated with blood pressure (BP) in Japanese men, but no data are available for Caucasians. Hence, we genotyped the IVS5+169C>T polymorphism of the (P)RR gene in 266 Caucasian men with normal or mildly elevated BP and without any medication. Office BP was measured according to current guidelines. Office and resting systolic BP was lower in C-allele than in T-allele carriers (P<0.05) of the (P)RR gene, with no difference in diastolic BP and heart rate. Serum aldosterone was also lower in C-allele than in T-allele carriers (P<0.05). These findings indicate that C-allele carriers have lower systolic BP than T-allele carriers. Thus, our data suggest that (P)RR influences BP regulation in Caucasian men, potentially through altered aldosterone release.