AAC (Augmentative and Alternative Communication) approach has long been applied in European and American countries, and more and more studies have shown that AAC can help communicate people with disabilities to develop communication skills. From 2016, the special education field also began to pay attention to AAC in special child education intervention in the application in China. Rett syndrome as a typical representative of children with multiple disabilities, AAC's approach has become a strong expectation of leading them across communication barriers and helping them overcome learning disabilities. Because of the multiple barriers, the daily life of children with RTT are seriously affected by the disease, so they are in urgent need of evidence-based treatment programs based on the effectiveness of the study. This project will carry out a three-month intervention training for four children with RTT. The children will receive half-day one-on-one and group classes in a multi-sensory environment. In the AAC participatory model, one-on-one intervening teachers assume the role of communication partners, and both RTT girls and communication partners are both assessed and trained for communication skills. The results of this project will also benefit other types of multiple barriers.