Functional maturation of human cerebellar structures was previously difficult to evaluate with positron emission tomography (PET) because of scanner resolution. Only vermis and cerebellar hemispheres could be reliably identified with 2-deoxy-2[18F]fluoro-D-glucose (FDG) PET. In the present study, we have used a new high resolution PET system, the Siemens EXACT-HR, to study, in depth, the patterns of glucose metabolism in various cerebellar structures. Due to the orientation of the cerebellar fissures which are important landmarks, the largest number of regions could be identified when the cerebellar regions were displayed on coronal planes. The high resolution PET images, together with magnetic resonance imaging (MRI) data and standard atlases, now allow identification of the following cerebellar structures: anterior vermis, posterior vermis, dentate nucleus, anterior lobe, posterior quadrangular lobule, superior semilunar lobule, inferior semilunar, gracile, and biventer lobules, tonsil, and cerebellar white matter. These cerebellar regions are displayed in an atlas format together with magnetic resonance images to allow easy identification. The present study is a prerequisite for detailed PET analyses of cerebellar metabolism in children with diseases of the cerebellum.