INTRODUCTION: Median nerve is formed in axilla by medial and lateral roots from medial and lateral cords of brachial plexus respectively. Anatomical variations of median nerve are not uncommon. Incidences of variation in lateral root is more common than that of the medial root. The additional lateral root of median nerve is of great academic and clinical significance as this finding will provide anatomical basis for clinical correlation in case of neuropathies & surgeries of upper limb. Also understanding the embryological stages in development of brachial plexus is important for explaining possible anatomical variants. AIM AND OBJECTIVES: This study was conducted to provide a thorough description of anatomical variation in formation of the lateral root of median nerve along with its embryological basis and clinical significance. MATERIAL AND METHODS: This study was conducted on 22 (20 male, 2 female) formalin fixed human cadavers available in the Department of Anatomy, Osmania Medical College, Koti, Hyderabad. RESULTS: Median nerve was formed in the axilla by one medial root & two lateral roots in one of the male cadaver among 22 cadavers that is in 2.27% cases and the additional lateral root joined the median nerve in middle third of arm. CONCLUSIONS: Anatomical variability in formation of the lateral root of median nerve does exist and significant in the management of surgical exploration of the axilla or arm and in the nerve blocks procedures of the brachial plexus as this being a peripheral nerve is more susceptible to be injured during operations. Injury to such a variant nerve in the proximal arm may lead to a number of manifestations. Possible clinical implications relating either to the surgical approach to the shoulder joint and entrapment syndromes are important and can be explained based on embryological basis.