Spinal muscular atrophy is an entity of neurodegenerative disorders at the anterior horn neuron of the spinal cord caused by telomeric survival motor neuron gene abnormality. There is no definitive treatment for spinal muscular atrophy, but recent reports have indicated the efficacy of intravenous injection, but not oral administration, of thyrotropin-releasing hormone (TRH). We treated an 18-year-old male patient with spinal muscular atrophy type III by oral administration of the thyrotropin-releasing hormone analogue, taltireline hydrate. His muscle strength increased significantly after the therapy, and he showed no clinical or laboratory identifiable adverse effects, including thyroid-stimulating hormone suppression that had been observed with intravenous thyrotropin-releasing hormone therapy. Oral administration of this thyrotropin-releasing hormone analogue should be noted as a promising therapy for spinal muscular atrophy.