Background and aims: Children with language impairments often experience difficulties with their socio-emotional functioning and poorly developed prosocial behaviour. However,the nature of the association between language impairment and difficulties with socio-emotional functioning remains unclear.The social cognition skills of a group of primary-aged children(6?11 years old) with Specific Language Impairment(SLI) were examined in relation to their teachers? ratings of socio-emotional functioning. Sample: Forty-two children with SLI were individually matched with 42 children for chronological age and non-verbal cognitive ability, and 42 children for receptive language ability. The children all attended mainstream primary schools or one Language Unit. Methods: Four aspects of social cognition were directly assessed: emotion identification, emotion labelling, inferring the causes of emotions, and knowledge of conflict resolution strategies.The children?s socio-emotional functioning was assessed using the Strengths and Difficulties questionnaire (SDQ), a standardised measure, completed by their teachers. Associations between children?s performance on tasks of social cognition and children?s socio-emotional functioning were explored. Results: Significant group differences were found for all social cognition tasks. The SLI group was rated to experience significantly more problems with socio-emotional functioning by their teachers than both control groups, indicating problems with all aspects of socio-emotional functioning. Social cognition and prosocial behaviour,but not language ability, predicted teacher- rated behavioural, emotional and social difficulties for the SLI group. Conclusion: The results challenge current understanding of socio-emotional functioning in children with SLI by pointing to the crucial role of social cognition and prosocial behaviour. Factors other than expressive and receptive language play a role in the socio-emotional functioning of children with SLI.