Background: Autism is a life-long developmental disability that prevents people from understanding what they see, hear, and otherwise sense resulting in severe problems with social interaction, communication, and behavior. The prevalence of autism in Egypt estimated to be 33.6% among children with developmental disabilities. Early intervention is effective to improve the quality of life for autistic child but single intervention is going to be insufficient to meet child's needs therefore, it was urgent to develop individualized comprehensive treatment program including behavioral, nutritional and educational approaches, this study aimed to assess the effectiveness of a language training program coupled with Feingold diet on developing autistic children` receptive language skills in centers caring for children with special needs at Mansoura city, and to assess knowledge and practice of caregivers regarding receptive language and Feingold diet. Quasi- experimental design was used to carry out this study at three centers caring for children with special needs including autism at Mansoura city in Dakahlia governorate. The sample size was (30) autistic children and their caregivers (30) distributed randomly into three intervention groups (language intervention group, Feingold diet intervention group and language + Feingold diet (coupled) intervention group)and children were chosen according to inclusion criteria, but care givers were chosen without any inclusion or exclusion criteria The study was conducted throughout preparation phase and operational phase including initial data collection, developing training programs, implementation of programs` sessions, and evaluating effectiveness of programs toward developing children` receptive language skills and increasing caregivers` knowledge and practice toward receptive language and Feingold diet. Non-significant differences were detected between pre-post interventions among children regarding to their performance on language training and their developmental level of receptive language skills of three groups. While there were a significant differences (P= 0.002), (P<0.001), between pre-post interventions for caregivers related to their knowledge and their practice about receptive language. Also there was a significant differences (P = 0.025) between pre-post interventions of caregivers knowledge related to Feingold diet. Conclusion: Although the coupled program of a language training with Feingold diet was effective in increasing caregivers` knowledge and practice about receptive language and Feingold diet, but it wasn`t effective in developing autistic children` receptive language skills.