Paraphrenia is a chronic psychotic disorder characterized by a strong delusional component with preservation of thought and personality. It was first introduced as a disorder associated with paranoid dementia and paranoia, but with less personality deterioration than schizophrenia and without fulfilling the clinical features of a delusional disorder. This classic diagnostic entity is not currently listed in main diagnostic systems, rendering delusional disorders difficult to classify in cases that resemble the concept of paraphrenia. We revisit the concept of paraphrenia through a critical review based on a clinical vignette of a patient followed at the psychiatry department of the University Hospital Center of São João.