Brachial neuritis is characterized by shoulder and arm pain followed by weakness and atrophy of affected muscles and sensory loss in the arm. Isolated sensory involvement of the brachial plexus is very rare. Diagnosis of brachial neuritis is usually based on clinical history and examination, with the confirmation by electrodiagnostic tests. A 72-year-old woman presented with numbness and tingling in the bilateral upper extremities. While nerve conduction examination revealed only sensory abnormalities of the bilateral upper extremities, magnetic resonance imaging (MRI) showed thickening and hyperintensity of the bilateral brachial plexus. We report a case of bilateral brachial neuritis with clinical and electrophysiological pure sensory involvement diagnosed using brachial plexus MRI. Although electrophysiological examination is thought to be the best diagnostic technique in the diagnosis of brachial neuritis, its findings sometimes indicate a distal lesion, while the involvement of the whole brachial plexus can be seen in MRI.