Migrant sensory neuritis, which was first proposed by Wartenberg, is very uncommon and only a few case reports have ever been published. We described one case of migrant sensory neuritis and discussed the pathogenesis of this disease. A 44-year-old man noticed numbness in the lateral aspect of the dorsum of the left foot in February 1985. Physically, there was hypoesthesia in the region of left sural nerve with positive Tinel's sign. During the next 4 years, pain, tingling sensation or hypoesthesia appeared in the regions of the right superficial radial nerve, right axillary nerve, left intercostal nerve, left lateral plantar nerve, digital nerve of the right second digit, left saphenous nerve, right superficial peroneal nerve, left superficial radial nerve, bilateral ulnar nerves and bilateral median antebrachial cutaneous nerves one after another in a migrating fashion. Tinel's sign was also positive at the right superficial radial nerve. In some occasions, decreased deep tendon reflexes were observed, but there had been no muscle weakness. Some nerves showed complete recovery, but others showed persistent involvement. Some nerves were affected repeatedly. Laboratory examination failed to clarify underlying disease except for mild liver dysfunction. Electrophysiological study showed reduced amplitude of the sensory nerve action potential (SNAP) of right sural nerve, left ulnar nerve, right superficial radial nerve and digital branch of right median nerve with preserved sensory nerve conduction velocity. SNAP of left sural nerve was absent. These findings mean the cause of the sensory disturbance is axonal degeneration rather than segmental demyelination. There were no abnormalities in motor nerve conduction study.(ABSTRACT TRUNCATED AT 250 WORDS)