The cerebellum is a highly organized neural structure essential for motor coordination, balance, motor learning, and cognitive processing. This chapter provides a comprehensive review of cerebellar neuroanatomy, including its three phylogenetic divisions: the archicerebellum (vestibulocerebellum), paleocerebellum (spinocerebellum), and neocerebellum (cerebrocerebellum). The uniform three-layered cortical architecture consists of the molecular layer, Purkinje cell layer, and granular layer, with Purkinje cells serving as the sole cortical output to the deep cerebellar nuclei (fastigial, globose, emboliform, and dentate). The cerebellum receives two principal afferent systems: climbing fibers from the inferior olivary complex and mossy fibers from diverse sources including the pontine nuclei, spinocerebellar tracts, and vestibular nuclei. Granule cell axons (parallel fibers) provide the primary intrinsic processing pathway. Functionally, the vestibulocerebellum regulates equilibrium and eye movements, the spinocerebellum controls ongoing movement execution and posture, and the cerebrocerebellum participates in motor planning and cognitive functions. Deep cerebellar nuclei integrate cortical and extracerebellar inputs to generate output via the three cerebellar peduncles. Clinical correlations include characteristic syndromes from lesions to each functional division, common pediatric tumors (medulloblastoma and pilocytic astrocytoma), and congenital malformations (Chiari malformations Types I–IV). Understanding cerebellar anatomy and function is fundamental for neurological diagnosis, localization of pathology, and comprehending the integration of motor and cognitive processing in the nervous system.