Extrapulmonary manifestations of Mycoplasma pneumoniae are well described, including a subset of central nervous system (CNS)-associated syndromes. In pediatric populations, frequencies of CNS sequelae occur in 0.1% to 7% of patients. Neurologic illness associated with M. pneumoniae, such as meningitis, encephalitis, polyradiculitis, Guillain-Barre, and stroke have been reported; however, the incidence of M. pneumoniae-associated organic brain syndrome is rare. We present the case of a 20-year-old midshipman with acute psychosis following resolution of M. pneumoniae pneumonia and review 6 other adult cases found in the literature. M. pneumoniae remains one of the most common causes of respiratory illnesses in the military recruit setting and therefore should always be suspected as an organic cause of mental status changes in young persons such as recruits, cadets, and midshipmen particularly with antecedent respiratory illnesses.