The aim of the current study was to predict mental health of the mothers of children with intellectual and developmental disabilities from the magnitude of their forgiveness. To fulfill the stated goal 88 mothers of children with intellectual and developmental disabilities by means of accessible sampling procedure, and Besharat mental health (2009) as well as Enright forgiveness inventories standardized by Ghobari Bonab et al. (2003) was given to them. Analysis of data using Pearson's correlation revealed that among mental health (psychological well-being and psychological distress) and all three dimensions of forgiveness a positive relation was found. In other words, individuals who were higher in forgiveness were more satisfied in their mental health. Multivariate regression also revealed that 23% of variations in psychological well-being by affective and cognation, and 20% of variations in psychological distress by cognation and behavioral component can be accounted by dimensions of their forgiveness. Theoretical implication and practical application of the findings have been delineated in the original paper.