The purpose of this study was to evaluate hemodynamics of intracranial blood flow for obtain clinically useful reference values and assess cerebral hemodynamics change with aging. 81 normal Korean subjects(age, 14$ hicksim∼ hicksim$70 years) examined who han no history of neurologic disease and the subjects divided into group A(age, 14$∼$39 years), group B(age, 40$∼$59 years) and group C(age, 60$∼$70 years). Transcranial doppler was use for measured the maximum velocity(Vmax), mean velocity(Vmean), pulsatility index(PI), resistive index(RI), stenosis index(SI) and depth of sample volume. Vmax was 99.1 1cm/s, Vmean was 63.57cm/s, PI was 0.85, RI was 0.56, SI was 31.94 and depth of sample volume was 52.35 in middle cerebral artery. Vmax was 85.54cm/s, Vmean was 52.52cm/s, PI was 0.82, RI was 0.55, SI was 34.48 and depth of sample volume was 73.62 in anterior cerebral artery. Vmax was 75.45cm/s, Vmean was 45.60cm/s, PI was 0.82, RI was 0.58, SI was 36.14 and depth of sample volume was 62.35 in posterior cerebral artery. Vmax was 70.44cm/s, Vmean was 47.07cm/s, PI was 0.87, RI was 0.58, SI was 29.83 and depth of sample volume was 75.23 in basilar artery Vmax was 63.92, Vmean was 42.42, PI was 0.89, RI was 0.58, SI was 29.89 and depth of sample volume was 66.65 in vertebral artery. Vmax and Vmean was significantly decreased with increasing age in middle cerebral artery, anterior cerebral artery, posterior cerebral artery, basilar artery and vertebral artery And PI and RI was significantly increased with increasing age in basilar artery and vertebral artery. And I suggest that transcranial doppler sonography can be used as one of useful clinical tool for detection of cerebral hemodynamics.