Organic psychosis refers to a group of diseases currently classified as “mental disorders due to a medical illness”, unlike the absence of specific organic causality that exists in primary disorders. These are secondary to long-term processes , which is necessary to re-evaluate frequently due to the association between age-related deterioration, comorbidity and the evolution of psychosis itself. We present the case of a patient with subarachnoid hemorrhage secondary to a ruptured arteriovenous malformation, who suffered from a slight change in behavior and decreased cognitive functions with subsequent evolution to dissociative symptoms, episodes of hypersomnia and disconnection from the environment, through assessment joint of specialties was reached the diagnosis of organic psychosis type schizophreniform disorder.