Capgras syndrome (CS), also called imposter syndrome, is a rare psychiatric condition that is characterized by the delusion that a family relative or close friend has been replaced by an identical imposter. Here, we describe a 69-year-old man with CS who presented to the Kemal Arikan Psychiatry Clinic with an ongoing belief that his wife had been replaced by an identical imposter. MRI showed selective anterior left temporal lobe atrophy. Quantitative EEG showed bilateral frontal and temporal slowing. Neuropsychological profiling identified a broad range of deficits in the areas of naming, executive function, and long-term memory. On the basis of these findings, we diagnosed frontotemporal dementia. This case demonstrates that CS can clinically accompany frontotemporal dementia.