Aims of this study were (i) to verify whether a deficit or a lack of self-awareness can lead to difficulties in assuming another person's perspective after a severe traumatic brain injury (TBI); (ii) to verify whether perspective-taking deficits emerge more from performance-based tasks than self-reports; and (iii) to evaluate the possible relationships between perspective-taking difficulties and some clinical, neuropsychological, neuropsychiatric, and neuroimaging variables. The Interpersonal Reactivity Index, Empathy Quotient, first-order false-belief, and faux pas written stories were administered to 28 patients with severe TBI and 28 healthy controls. The Awareness Questionnaire was also administered to TBI patients and their caregivers. Patients were split into 2 groups (impaired self-awareness vs adequate self-awareness) on the basis of the discrepancy Awareness Questionnaire score. Both TBI groups obtained lower scores than healthy controls on the Fantasy subscale of the Interpersonal Reactivity Index, the reality question of the false-belief stories, and the memory questions of the faux pas test. Only impaired self-awareness patients tended to obtain lower scores in first-order false-belief detection. Impaired self-awareness patients also performed significantly worse than both healthy controls and adequate self-awareness patients on the faux pas tasks. The analysis suggests a causal relationship between low self-awareness and perspective-taking difficulties in this population of patients.