Aim to study the variant Flexor Carpi Ulnaris muscle and associated neurovascular variations. 100 upper limbs of 50 donated embalmed cadavers (45 males & 5 females) of age group ranging from 70 to 80 years were dissected in the department of Anatomy at K. J. Somaiya Medical College, Sion, Mumbai, INDIA. The accessory slip of flexor carpi ulnaris muscle was observed in 2 specimens. The associated neurovascular variations were also observed in 2 specimens. The photographs of the variations were taken for proper documentation. The accessory slip of flexor carpi ulnaris muscle was observed in 2 specimens. The accessory slip of flexor carpi ulnaris originated from lower part of it’s tendon and got inserted into the palmar aponeurosis and the tendon of palmaris longus muscle. The total length of flexor carpi ulnaris muscle was 26 cm, with a muscular belly of 22 cm and 3.5 cm of width and 0.5 cm of thickness. In one specimen the total length of an accessory slip of flexor carpi ulnaris muscle is 2 cm, and thickness 0.5 cm and in another specimen the total length of an accessory slip of flexor carpi ulnaris muscle is 4 cm, and thickness 0.5 cm. The accessory muscle is located between the tendon of flexor carpi ulnaris muscle and palmaris longus muscle. The associated neurovascular variations were also observed in 2 specimens. The accessory slip of flexor carpi ulnaris muscle was associated with incomplete superficial palmar arch in one specimen and the accessory slip of flexor carpi ulnaris muscle was associated with high division of ulnar nerve in another specimen. The knowledge of such accessory slip of flexor carpi ulnaris muscle and associated neurovascular variations may be clinically important for plastic surgeons doing flap surgeries and for the surgeon dealing with cubital tunnel syndrome.