Supination and pronation deformity of the forearm are common squeal of obstetric brachial palsy. Initially, forearm deformity may be reduced passively, with time and growth – usually after 2 years of age – the interosseous membrane begins to retract and the deformity cannot be passively corrected. In the supination position of the forearm the interosseous membrane space of the forearm reduces and the interosseous becomes retracted in its strong descending radio-ulnar fibers. Supination contracture of the forearm is a very disabling deformity. Owing to its presence, many common activities in daily life, such as dressing, eating and writing, require elbow flexion and abduction plus internal rotation of the shoulder.In these literature we review the anatomical consideration and pathophysiology of supination and pronation deformity of the forearm and their management.