Background: Sacralization of L5 is a congenital anomaly, in which the lumbar vertebra, mainly its transverse process, gets fused or semi-fused with the sacrum or the ilium or to both. This fusion can occur in one or both sides of the body. Sacralization leads to fusion of the L5 (fifth lumbar vertebra) and S1 (first sacral vertebra) and the inter-vertebral disc between them may be narrow. Sacralization of lumbar vertebra may be asymptomatic but is not always clinically insignificant. While sacralization may not affect at all, it can cause problems in some cases. Sacralization may be at times associated with problems in biomechanics and affect the ways of movement and posture control. Sacralization may also be an important consideration in disc surgeries. This study has been carried out to find out prevalence of sacralisation of transverse process of fifth lumbar vertebrae.Methods: The present study of transverse sacralisation of fifth lumbar vertebra was carried out on 35 randomly selected patients. The sample consisted of patients undergoing CT scan for abdominal complains. Bone window of all patients were evaluated to look for lumbosacral transitional vertebra.Results: The prevalence of transverse sacralization of lumbar vertebra turned out to be 25.7% out of which Castellvi type IIb was found to be most common, accounting for 33.3% cases. 5.7% comprised the group of normal variant (Castellvi’s type I) and 68.6% were normal. Conclusions: It is important to determine lumbosacral transitional vertebra as it can affect spinal movement and put excess stress on the lumbar vertebrae and in between disc. Moreover it can have a bearing on counting of vertebral levels specially during planning of spinal surgey.