Background: Psycho-education may have a positive effect on family caregivers of clients with mental disorders, and promote positive psychological states such as hope. The present study aims to investigate the effect of virtual social network-based psycho-education on the hope of family caregivers of clients with severe mental disorders. Method: This study is a quasi-experimental research with a control and experimental groups. The participants of the study were 72 family caregivers of clients with severe mental disorders (36 in each group). Data were collected using demographic questionnaire and Adult Hope Scale before the study, immediately after the end of the training (first post-test), and 4 weeks afterwards (second post-test). The experimental group received psycho-education through Telegram App for four weeks. Results: The results of the demographic questionnaire showed that both groups were homogeneous. The results of the Adult Hope Scale indicated that the mean score of both control and experimental groups were statistically significant and increased in the experimental group (P < 0.001). In addition, the changes of hope score in the experimental group were statistically significant in the first post-test than the pre-test, and in the second post-test than the first post-test and pre-test (P < 0.001). Conclusions: The findings of this study suggested that virtual social network-based psycho-education promotes the hopes of the family caregivers of clients with severe mental disorders. Due to the low cost and fast access of people to virtual networks, the content of this educational program can be widely used for family caregivers.