Cervical vertebrae are having foramen transversarium in their transverse process. Foramen transversarium's dimensions and its variations are important for clinicians while handling vertebro basilar insufficiency cases and also useful for spinal surgeons in spinal decompression procedures like foraminectomy, foraminotomyMaterials & Methods: The present study was done in 90 sub axial vertebrae (C 3 to C 7 ) which was collected from Rajah Muthiah Medical College, Chidambaram. Among 90, 56 were typical type and 34 were seventh cervical vertebrae. Damaged vertebrae were excluded. Antero posterior length, transverse length & depth of foramen transversarium were measured using double tipped compass and digital vernier caliper. Double foramens and absent foramens were noted. Result:The average antero posterior length of foramen transversarium of typical cervical vertebrae and seventh cervical vertebrae were 5.45 mm ± 0.12 mm and 5.66 mm ± 0.88 mm respectively. The average transverse length of foramen transversarium of typical and seventh cervical vertebrae was 6.72 mm ± 0.22 mm and 6.76 mm ± 0.08 mm respectively. Conclusion:Anatomical knowledge on the dimensions of foramen transversarium and its variations are important for clinicians and neurologists for the various clinical conditions and spinal decompression procedures.