Objective: Attention to adaptation and the factors influencing it is important for promoting maternal health and improving parent-child relationships, especially in mothers of children with intellectual disability. The purpose of this study was to investigate the relationship of acceptance and action and prospects for the future with psychological flexibility and adaptation in mothers of children with intellectual disability. Method: This study employed a descriptive-correlational designed and path analysis. The population consisted of all mothers of children with intellectual disability aged 12-16 years and studying in exceptional schools of Mashhad, Iran, in 2016-2017. A sample of 217 mothers was selected by convenience sampling. The data were analyzed in LISREL using path analysis which includes a set of regression equations. Results: By examining the fitness indices and considering the value of RMSEA <0.08 and SRMR <0.08, the fit of the model was desirable. Also, in other indices (e.g. NNF NFI, NNFI, CFI, RFI, and IFI), results were >0.9, indicating the acceptable fit of the model. Conclusion: Prospects for the future and acceptance and action both directly and indirectly increase adaptation in mothers of children with intellectual disability. Therefore, these mothers differ in terms of adaptation according to the degree of acceptance and action and psychological flexibility, and adaptation can be promoted in them by interventions designed to enhance these variables