Among solid tumours, medulloblastoma is the most common of the posterior fossa neoplasms, given that it represents 15%-20% of childhood brain tumours. The main aim of the present study was to assess the effects of action observation training on the activities of daily living (ADL) and the manipulation skills of children with acquired brain injury secondary to an oncological process. Methods: We recruited a consecutive convenience sample of 5 patients diagnosed with acquired brain injury secondary to an oncological process. ADL and manipulation skills were assessed using the ABILHAND-Kids and Jebsen-Taylor Hand Function Test, respectively. After conducting the initial evaluation, we planned the intervention, which lasted 10 weeks and consisted of 40 sessions for each participant, 10 in the occupational therapy department and 30 at home. After completing the intervention, we re-evaluated the main variables. Results: Overall, the results of the postintervention ABILHAND-Kids questionnaire showed a 5-point improvement, with a statistically significant difference and a large effect size. Eighty per cent of the sample showed better results in the total score, with differences between 4 and 8 points. In relation to manual dexterity, as measured by the Jebsen-Taylor Hand Function Test, there were no significant changes, except in one of the participants. Conclusion: It appears that action observation training can elicit positive changes with respect to the development of ADL, but the influence on manual dexterity was almost nonexistent.