Neuromyelitis optica or Devic's syndrome is an uncommon demyelinating disorder that preferentially attacks the spinal cord and optic nerves. Although it is well described in adults, childhood neuromyelitis optica has rarely been reported in the literature and is frequently misdiagnosed as severe multiple sclerosis. Recently, a serum immunoglobulin G test for neuromyelitis optica has become available which may clarify and accelerate the diagnosis. This report describes a child with recurrent myelitis and an elongated spinal cord lesion who was found to have positive neuromyelitis optica autoantibody. We believe that neuromyelitis optica autoantibody testing should be performed in cases of pediatric transverse myelitis with multiple vertical segments or recurrence.