Objective: The purpose of this study was to examine the effectiveness of group coping skills training on stress and hopelessness level in mothers of children with intellectual disabilities (ID). Method: In this quasi experimental research, mothers of children with ID referred to Welfare Organization Centers, and 44 mothers from this population having the required criteria were randomly selected, and randomly assigned into experimental and control groups. Experimental group received 12 session for coping skills training (each session 90 min), while the control group received no intervention. Research instruments were Questionnaire on Resources and Stress (Fredric, 1983) and Beck Hopelessness Scale. Results: The results showed that coping skills training could decreased stress and hopelessness level of mothers of children with ID. Conclusion: Coping skills training could be suggested as a treatment for these mothers.