This study was conducted with two groups (training and control) using a pretest/post-test design to determine the effect of cognitive behavioral approach-based psychoeducation on the levels of coping with hopelessness and stress of parents of children with cancer. The data were collected using the "Personal Information Form", "Coping with Stress Scale" and "Beck Hopelessness Scale." The training was given as a total of eight sessions of individual training every 2 weeks. The study showed that after the training, the training group scored significantly lower than the control group in the sub-dimensions of helpless and submissive approach in coping with stress and hopelessness levels and scored higher in the sub-dimensions of self-confident approach, optimistic approach, and seeking social support approach. It was found that cognitive-based psychoeducation had an effect on increasing the ways of coping with stress and decreasing the hopelessness levels of parents of children with cancer.