Posterior fossa extends from tentorium cerebelli to foramen magnum and posterior fossa tumours are more common in children than in adults. Since posterior fossa is a critical location with limited space, even small tumours produce significant morbidity and mortality. The advent of Magnetic Resonance Imaging (MRI) has revolutionised the diagnosis and management of brain tumours. OBJECTIVESTo study the demographic profile and assess the distribution, features, localisation, and extent of posterior fossa neoplasms by MRI and to correlate the tissue characterisation by MRI with that of histopathological examination. MATERIALS AND METHODSA prospective study was done on 90 patients who were diagnosed to have posterior fossa neoplasm by magnetic resonance imaging from January 2014 to November 2015. They were followed up till surgery or biopsy for confirmatory histopathological diagnosis. The final diagnosis were correlated followed by analysis of the present study by comparing with previous similar studies from various literature. RESULTSThere was an overall male predominance with Male: Female ratio of 1.5:1. Among adults, extra-axial tumours (68%) were more frequent than intra-axial ones (32%) with vestibular schwannoma (37%) being the commonest lesion. Most common intra-axial tumour was metastasis (13%) and most common primary intra-axial tumour was haemangioblastoma (8%). Among paediatric age group, intra-axial tumours (83%) were commoner than extra-axial ones (17%) with low-grade astrocytoma (38%) as the commonest lesion followed by medulloblastoma (29%) and ependymoma (17%). Overall, 6 cases were misdiagnosed by MRI as glioma and turned out to be tuberculoma CONCLUSIONMRI proves to be a valuable modality of imaging in accurately evaluating the morphologic distribution of various intra-and extra-axial tumours in the posterior fossa. MRI can correctly diagnose 100% of extra-axial tumours and 85% of intra-axial lesions. Main tumour mimics of posterior fossa are tuberculoma and pyogenic abscess.