Objectives: Within the realm of social cognition, brain injury research has increasingly focused on a specific element of social competence: the ability to attribute mental states (e.g. thoughts, feelings, desires, and beliefs) in order to explain and predict people’s behaviour. This study was conducted in order to investigate this component of everyday social understanding commonly referred to as ‘theory of mind’ (ToM) in post-stroke individuals. The aims were to investigate whether lesions to particular areas of the brain are more detrimental to ToM ability compared to others and investigate the relationship between ToM ability and executive function following stroke. Design: This study was of mixed factorial design and compared the performance of stroke patients (right-hemisphere stroke, n = 15; left-hemisphere stroke, n = 15) to that of controls (n = 40) matched for age, years of education and IQ on tasks believed to measure theory of mind and executive function. Results: Significant differences were found between the groups’ performances on the ToM task with results suggesting lesions to the right hemisphere as being particularly detrimental to ToM ability. Positive associations were found between performance on the ToM task and measures of executive function, although deficits in executive functioning could not fully account for the difficulties shown by stroke patients on the ToM task. Conclusions: The findings of this study suggest that the right hemisphere damage following stroke is particularly detrimental to an aspect of social cognition commonly referred to as ToM. Impaired ability to attribute mental states to others can interfere with how individuals use information conveyed through social interaction and can, in turn, affect psychosocial functioning, disrupt interpersonal relationships, and lead to reduced quality of life. The findings of this study are discussed in relation to implications for the individual and rehabilitation progress.