Pure Ulnar Nerve Leprosy Abscess-Palsy (UNLAP) is uncommon infectious disorder caused by Mycobacterium leprae. This study demonstrates a case report of isolated tubercloid leporsy neuritis of right ulnar nerve presented by sudden onset non-inflammatory tender oval swelling over elbow joint and complicated by acute motor and sensory deficit, posing a diagnositic management confusion. High resolution ultrasonography and maganatic resonance imaging (contrast and non-contrast) were performed. Swelling was expolred and excised after abscess evacuation with complete external neurolysis of ulnar nerve in the cubital tunnel. Specimen was taken for histopathological investigation which revealed positive special staining for leprosy. A typical presentation of leporsy must be taken into consideration to detect the proper line of treatment.