Purpose Evaluation of the effect of supportive expressive discussion groups on loneliness, hope and quality of life in breast cancer survivors. Methods A randomized control trial including breast cancer patients who had completed chemotherapy and randomly allocated into two groups: intervention (n = 41) and control (n = 40). The intervention consisted of twelve weekly 90‐min sessions for groups of six to eight breast cancer survivors. Data were obtained pre‐to ‐post the intervention and at 8‐week follow‐up. The data were analyzed using a repeated‐measures analysis of variance (ANOVA). Results The findings revealed a significant reduction in loneliness scores (F = 69.85, p < 0.001), promotion in total hope (F = 20.8, p < 0.05) and enhancement in quality of life from pre‐ to post‐intervention, and then over the 8‐week follow‐up period in the intervention group, while scores of control participants did not show this pattern during the study. The strongest effects were found for global quality of life (effect size) = 0.59), for future perspectives (effect size = 0.51), emotional functioning (effect size = 0.35) and social functioning (effect size = 0.31). Conclusion The intervention was effective on loneliness, hope and quality of life in the intervention group. The intervention needs further evaluation in a larger study and with other cancer types. Copyright © 2016 John Wiley & Sons, Ltd.