Cerebral blood flow (CBF) images obtained using Xe-CT have a much higher spatial resolution than SPECT or PET images. The regional CBF (rCBF) of deep brain regions, the basal ganglia and thalamus, was able to be measured using Xe-CT in 6 subjects. Average rCBF was 87.1 +/- 20.7 ml/100 g/min in the caudate nucleus, 83.5 +/- 15.8 ml/100 g/min in the putamen, 50.0 +/- 8.7 ml/100 g/min in the globus pallidus and 88.9 +/- 12.4 ml/100 g/min in the thalamus. The average rCBF value of the globus pallidus was lower than the values of the caudate nucleus, putamen and thalamus. These observations may be explained by reduced cellularity of the globus pallidus in comparison to the other regions. SPECT and PET are not able to clearly demonstrate the globus pallidus on CBF images. However, precise rCBF values can be measured in the globus pallidus using Xe-CT.