Background: The present study investigates the effect of resilience training in improving the ability to cope with stress and hope of mothers with cancer children. Methods: In this interventional study, 70 mothers parenting children with cancer were selected as available and randomly classified into the control and experimental groups. The mothers of the two groups completed the parenting stress and hope questionnaire. In the test group, nine sessions of resilience training were held by the researcher for 60 min. One month after the intervention, they were again asked to complete the parenting stress and hope questionnaires. Moreover, in the control group, the mothers completed the parenting stress and hope questionnaires again 2 months later without any intervention. Result: The difference between the average scores of hope and parental stress showed that the mean score of hope in the intervention and control groups increased by about 5.45 and 2.74 units, and the hope variable was improved in both groups. The mean score of parental stress in the intervention group decreased by 39.62 units. However, in the control group, it increased by 2.45 units, and parental stress in this group declined. Conclusion: Resilience training significantly reduced the level of parental stress and increased the level of hope in the mothers of the test group. Therefore, it is recommended to use resilience in reducing the level of parental stress and increasing the hope level of mothers with children with cancer.