Background: This study examines the utility of Pearlin's caregiving stress model for understanding the caregiving satisfaction of elderly mothers of adult children with intellectual disability. Methods: Mothers living in Seoul, Kyonggi, and Incheon who were 55 years of age or older and providing care for adult children with intellectual disability aged 18 or above were selected purposively from community rehabilitation centre users. A total of 392 participants responded to the survey. The structural equation modelling method was used to evaluate the suitability of the stress process model and to test the hypotheses. Results: The stress model proved to be a good fit to the data. The results showed that a mediating variable--a problem-centred coping strategy--transmitted the effect of stress variables such as recognition of ageing, establishment of permanency planning, and worries about the future on caregiving satisfaction. The relationship of adult children with intellectual disability also transmitted the effect of establishment of permanency planning on caregiving satisfaction. However, an indirect effect of an emotion-centred coping strategy was not shown. Conclusions: The findings of this study shed light on the development of intervention strategies for elderly mothers who provide care permanently to adult children with intellectual disabilities.