Cognitive training (CT) programmes have gained popularity, but their efficacy remains debated. This study evaluates the impact of technology-based CT intervention on cognitive skills in adolescents with autism spectrum disorder and/or mild intellectual disability, aiming to improve cognitive functioning. Four adolescents with autism spectrum disorder and/or mild intellectual disability participated in a 16-week home-based CT programme, undergoing neurocognitive assessments both before and after the intervention. The programme targeted a range of cognitive skills, including working memory, attention, inhibitory control and cognitive flexibility. The findings demonstrated significant improvements in spatial and visual working memory, attention, inhibitory control and cognitive flexibility among the participants. We conclude that technology-based CT interventions show promise in enhancing cognitive functioning and may contribute to improved educational outcomes for adolescents with autism spectrum disorder and/or mild intellectual disability.