Background: Dialectic behaviour therapy (DBT) has been widely used with individuals diagnosed with borderline personality disorder who exhibit severe emotional and behavioural dysregulation. There is a paucity of research in assessing the effectiveness of DBT with forensic clients with intellectual disability (ID). Methods: This pilot study aims to evaluate the effectiveness of the DBT group skills training programme adapted particularly for offenders with ID. Six participants completed the 13-week adapted DBT group skills training programme. All participants exhibited challenging behaviours and have a history of prior charges or convictions for violent crimes. The study conducted pre- and post-tests using instruments that measured dynamic risks, relative strengths, coping skills and global functioning. Results: The study result showed improvement across all measures. A decrease in the level of risks, increase in relative strengths and general improvement in overall functioning were found significant. The results were promising particularly as a stand-alone adapted DBT group skills training programme for this client group.