Aim:The aim was to study topography and variability in the origin of anterior interosseous nerve. The objectives were to study the branching pattern of the anterior interosseous nerve supplying the flexor digitorum profundus, flexor pollicis longus, and pronator quadratus muscles. Material and Methods:The present study included 70 formalin-fixed upper limbs of adult human cadavers. The origin of the anterior interosseous nerve was categorized into 3 types. The morphometric data obtained in this study were represented as mean± SD and the dimensions were given in millimeter. The measurements were compared statistically by using ‘EZR software, version 1.38, 2019’. The ‘paired t-test’ was applied and the ‘p’ value less than 0.05 was considered as statistically significant.Results:It was observed that the origin of the anterior interosseous nerve was extremely variable. It was ranging from the mid-epicondylar point of the elbow joint up to as below as 86mm from it. The distance of its origin from the midpoint of the pronator teres muscle ranged between 70mm above the pronator teres muscle to 22mm below it. In one of the forearms, the median nerve supplied the medial two tendons of the FDP, instead of the ulnar nerve.Conclusion:The present study provided additional information about the origin, topography, and distribution of the anterior interosseous nerve. The data will provide further insight into the causes of nerve compression syndromes. It will also help in planning the surgical approach into the distal humerus, elbow joint, and proximal ends of radius and ulna, without causing any nerve injury.