Study aim: To evaluate the effectiveness of a structured group-based music therapy program in improving sensory processing patterns and social skills in children aged 6–12 years with Autism Spectrum Disorder, compared to group-based social skills training without music. Design: Two‑arm, parallel‑group, randomized trial of 20 participants with open‑label intervention and blinded data analysis, single‑center. Settings and conduct: The trial will take place at the Occupational Therapy Department of Imam Hossein Hospital in Tehran, Iran. Children will be recruited from outpatient clinics. It is an open-label trial for participants and therapists, but outcome assessment will be blinded, with an independent analyst conducting all analyses without knowing group allocation. Participants/Inclusion and exclusion criteria: Inclusion criteria: - Children aged 6–12 years - Clinical diagnosis of ASD based on DSM-5 by a qualified child and adolescent psychiatrist - Stable physical health - Basic communication abilities for group participation - Informed consent from parent/legal guardian Exclusion criteria: - Uncontrolled neurological disorders (e.g., epilepsy) - Significant hearing or vision impairment - Severe behavioral problems preventing group participation - Participation in intensive music therapy in the past 6 months - Family unwillingness to attend scheduled sessions Intervention groups: Group-based music therapy program, 14 sessions (30–45 minutes each), including structured welcome and closing songs, rhythmic exercises, instrument playing, singing, and movement-based activities designed to stimulate sensory processing and promote social interaction. Main outcome variables: Sensory processing profile score — measured with the Children’s Sensory Profile‑2 Social responsiveness score — measured with the Social Responsiveness Scale‑2