Obsessive-compulsive disorder (OCD) is a severe, highly prevalent and chronically disabling disorder that usually emerges during childhood or adolescence. Neuroimaging studies play an important role in advancing our understanding of the pathophysiology of OCD and in developing neurocircuitry models of this psychiatric illness. This paper provided an updated, comprehensive review and analysis of the relevant literature on baseline functional and structural neuroimaging studies of OCD in both paediatric and adult patients. The neuroanatomical findings were presented in the context of two models: executive dysfunction, which implicates the dorsolateral prefrontal cortex, caudate nucleus, thalamus, and striatum; and modulatory control, which implicates the orbitofrontal and medial prefrontal cortex and the cingulate gyrus. Neuroanatomical findings were not consistent across all studies, and limitations were examined. Recommendations for future research directions and the implications of the results for improved treatment were explored.