The study aimed to explore whether McCubbin and Patterson’s Double ABCX model of stress and adaptation can promote a better understanding of the impacts of social support, definition of the stressor and coping strategies on stress and adaptation of the primary caregivers of Intellectually Disabled (ID) children above and beyond the effects of other factors. Structured Interview Schedule, Perceived Stress Scale (Keya, 2006) and Social Adjustment Scale (Mahmuda & Parvin, 2005) were administered on 130 caregivers of ID children and 140 caregivers of typically developing children recruited conveniently. Findings reveal that stress and adaptation of the caregivers of ID children were significantly positively associated (r = .429, p < .01). Significant variations in stress and adaptation of the caregivers of ID children were found in terms of children’s disability types (F = 14.50, df = 4/120, p < .001 for stress; F = 11.92, df = 4/120, p < .001 for adaptation) and severity of disability (F = 5.21, df = 1/120, p < .05 for stress; F = 11.14, df = 1/120, p < .01 for adaptation). Factors of the Double ABCX model of stress and adaptation created significant variations in stress (F = 17.94, df = 3/121, p < .001) and adaptation (F = 9.96, df = 3/121, p < .001) of the caregivers of ID children above and beyond the effects of other factors. The findings suggest that the Double ABCX model is valuable in understanding stress and adaptation of the primary caregivers of ID children.