Variations of venous pattern in the arm are common. In this case report, we present a variation of brachial vein (BV) and lateral root of median nerve (LRMN). During routine educational dissections of axillary region, it was observed that a fenestrated BV was perforated by LRMN in the right arm of an old male cadaver. LRMN was not exposed to compression as itpassed through the fenestration. It then joined the medial root of the median nerve to form the median nerve. The fenestrated segment of BV was narrow. However, BV coursed normally beyond this segment. There was no other anatomical variation in BV and LRMN both prior to the fenestrated segment and beyond it. Veins of the upper limb are commonly used fortotal parenteral nutrition, therapeutic invasive procedures, blood samples, blood transfusion, and catheterization and occasionally for grafting procedures. A large number of invasive procedures, both diagnostic and therapeutic are carried outusing veins of the upper limb, particularly in and distal to the axillary region. Classic and variational anatomy of the upperlimb is important with regards to surgical exposure of vessels in this region. Perforation of BV by the LRMN is a rare variation. Consequently, we think that it is important for the surgeons to keep this variation in mind in order to avoid possiblecomplications such as nerve injury.