A twenty-six year old man was admitted for febrile atypical pneumoniae. Few hours later, he presented an acute flaccid paraplegia with dorsal pain. Cerebrospinal fluid analysis showed a high leukocyte count with raised protein level. Neuroradiological examinations (myelography and MRI) were normal. Seric immunological disorders were reported. High complement-fixing antibody titers to Mycoplasma pneumoniae were found in the serum and in the CSF. The patient was treated with antibiotic and corticosteroids. He improved dramatically within one month. Neurological complications of Mycoplasma pneumoniae infections have been described (meningoencephalitis, meningitidis, polyradiculoneuropathies, cerebellar ataxia, cranial nerve palsies). Nineteen cases of transverse myelitis induced by Mycoplasma pneumoniae have been previously reported. Pathophysiological mechanisms of nervous system complications induced by Mycoplasma pneumoniae were discussed. Vascular mechanisms, direct invasion by the pathogen, toxic, immunological causes were examined.