Background: Children diagnosed with intellectual difficulties experience difficulties with narrative skills, due to limited syntactic knowledge. The Colourful Semantics approach with thematic roles and a colour coding system may encourage syntactic development in children experiencing intellectual disabilities. Aim: To evaluate the effectiveness of using the Colourful Semantics approach to develop narrative skills in Sri Lankan Tamil-speaking children diagnosed with intellectual difficulties. Methods: Thirty Sri Lankan Tamil-speaking children identified with intellectual difficulties were included. The Colourful Semantics approach was offered twice a week for 6 weeks, facilitated by the class teachers. Pre- and post-intervention narrative skill assessments were undertaken and analysed for content and syntactic structures. Results: The results indicate positive changes post-intervention on the qualitative and quantitative narrative skills measures undertaken on content and syntactic structures. Conclusions and Implications: The Colourful Semantics approach is an effective therapy approach to support development of narrative skills in children with intellectual difficulties.